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Changes between Version 114 and Version 115 of ProjectOptions

Timestamp:: Nov 12, 2011, 5:11:03 AM (12 years ago)
Author:: cries
Comment:: sched/sched_config.cpp:43:const int MAX_NCPUS = 64; (Revision: 24340)

Legend:

: Unmodified
: Added
: Removed
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ProjectOptions

-                      v114
+                      v115
 = Project configuration =
+The following elements in the `<config>` section of your [ProjectConfigFile config.xml] file
+control various aspects of your project.
+Booleans default to false, and can be expressed as
+The following elements in the `<config>` section of your [wiki:ProjectConfigFile config.xml] file control various aspects of your project. Booleans default to false, and can be expressed as
 {{{
 <tag>1</tag>  (true)
 …
 <tag/>        (true)
 }}}
 == Scheduler ==
+These options control how jobs are dispatched to clients.
+This is also affected by the parameters you
+pass to the [BackendPrograms feeder].
+These options control how jobs are dispatched to clients. This is also affected by the parameters you pass to the [wiki:BackendPrograms feeder].
 === General ===
 {{{
 <ban_cpu>regexp</ban_cpu>
 }}}
 Any host for which p_vendor<tab>p_model matches the given regular expression will not be sent jobs.
+This is a POSIX extended regular expression.
+Any host for which p_vendor<tab>p_model matches the given regular expression will not be sent jobs. This is a POSIX extended regular expression.
 {{{
 <ban_os>regexp</ban_os>
 }}}
 Any host for which os_name<tab>os_version matches the given regular expression will not be sent jobs.
+This is a POSIX extended regular expression.
+Any host for which os_name<tab>os_version matches the given regular expression will not be sent jobs. This is a POSIX extended regular expression.
 {{{
 <distinct_beta_apps>0|1</distinct_beta_apps>
 }}}
+If set, [AppFiltering user application selection] applies to [BetaTest beta test applications] as well as others.
+If set, [wiki:AppFiltering user application selection] applies to [wiki:BetaTest beta test applications] as well as others.
 {{{
 <homogeneous_redundancy>N</homogeneous_redundancy>
 }}}
+If zero (default) don't use the [HomogeneousRedundancy homogeneous redundancy] mechanism.
+Otherwise, specifies the granularity of host classification (1=fine, 2=coarse).
+(Note: you may also specify this on a per-application basis).
+If zero (default) don't use the [wiki:HomogeneousRedundancy homogeneous redundancy] mechanism. Otherwise, specifies the granularity of host classification (1=fine, 2=coarse). (Note: you may also specify this on a per-application basis).
 {{{
 <ignore_delay_bound/>
 }}}
 By default, results are not sent to hosts too slow to complete them within delay bound.
+If this flag is set, this rule is not enforced.
+By default, results are not sent to hosts too slow to complete them within delay bound. If this flag is set, this rule is not enforced.
 {{{
 <multiple_clients_per_host>0|1</multiple_clients_per_host>
 }}}
+Set this if some of your hosts run multiple BOINC clients simultaneously
+(this is the case on projects that use Condor and/or grid resources,
+which require each client to use only 1 CPU).
+If set, the scheduler will skip a check that tries to locate the host
+based on its IP address.
+Set this if some of your hosts run multiple BOINC clients simultaneously (this is the case on projects that use Condor and/or grid resources, which require each client to use only 1 CPU). If set, the scheduler will skip a check that tries to locate the host based on its IP address.
 {{{
 <nowork_skip> 0|1 </nowork_skip>
 }}}
+If the scheduler has no work, it replies to RPCs without doing any database access
+(e.g., without looking up the user or host record).
+This reduces DB load, but it fails to update preferences when users click on Update.
+Use it if your server DB is overloaded.
+If the scheduler has no work, it replies to RPCs without doing any database access (e.g., without looking up the user or host record). This reduces DB load, but it fails to update preferences when users click on Update. Use it if your server DB is overloaded.
 {{{
 <prefer_primary_platform> 0|1 </prefer_primary_platform>
 }}}
+Send hosts app versions for their primary platform if one exists;
+e.g. if a host is 64-bit, don't send it a 32-bit CPU version if a 64-bit CPU version exists.
+Use this option only if you're sure that your 64-bit versions are faster than the 32-bit versions.
+Send hosts app versions for their primary platform if one exists; e.g. if a host is 64-bit, don't send it a 32-bit CPU version if a 64-bit CPU version exists. Use this option only if you're sure that your 64-bit versions are faster than the 32-bit versions.
 {{{
 <report_grace_period>x</report_grace_period>
 }}}
+A "grace period" for task reporting.
+A task is considered time-out (and a new replica generated)
+if it is not reported by client_deadline + x.
+A "grace period" for task reporting. A task is considered time-out (and a new replica generated) if it is not reported by client_deadline + x.
 {{{
 <user_filter>0|1</user_filter>
 }}}
+If set, use the "batch" field of workunits to select which user is
+allowed to process the job.
+If batch is nonzero, only send the job to the user with that ID.
+If set, use the "batch" field of workunits to select which user is allowed to process the job. If batch is nonzero, only send the job to the user with that ID.
 {{{
 <workload_sim>0|1</workload_sim>
 }}}
+Use a more expensive, but more accurate, method to decide whether
+hosts can complete jobs within their delay bound.
+Use a more expensive, but more accurate, method to decide whether hosts can complete jobs within their delay bound.
 === Job limits ===
 …
 <one_result_per_user_per_wu/>
 }}}
+If set, send at most one instance of a given job to a given user.
+This increases the effectiveness of replication-based validation
+by making it more difficult for hackers to get all the instances of a given job.
+If set, send at most one instance of a given job to a given user. This increases the effectiveness of replication-based validation by making it more difficult for hackers to get all the instances of a given job.
 {{{
 <one_result_per_host_per_wu/>
 }}}
+If present, send at most one result of a given workunit to a given host.
+This is weaker than `one_result_per_user_per_wu`;
+it's useful if you're using homogeneous redundancy
+and most of the hosts of a particular class belong to a single user.
+If present, send at most one result of a given workunit to a given host. This is weaker than `one_result_per_user_per_wu`; it's useful if you're using homogeneous redundancy and most of the hosts of a particular class belong to a single user.
 {{{
 <min_sendwork_interval> N </min_sendwork_interval>
 }}}
+Minimum number of seconds between sending jobs to a given host.
+You can use this to limit the impact of faulty hosts.
+Minimum number of seconds between sending jobs to a given host. You can use this to limit the impact of faulty hosts.
 {{{
 …
 <max_wus_in_progress_gpu> M </max_wus_in_progress_gpu>
 }}}
+Limit the number of jobs in progress on a given host
+(and thus limit average turnaround time).
+Starting with 6.8, the BOINC client report the resources used by in-progress jobs;
+in this case, the max CPU jobs in progress is '''N*NCPUS'''
+and the max GPU jobs in progress is '''M*NGPUs'''.
+Otherwise, the overall maximum is '''N*NCPUS + M*NGPUS)'''.
+See the following section for a more powerful way of expressing
+limits on in-progress jobs.
+Limit the number of jobs in progress on a given host (and thus limit average turnaround time). Starting with 6.8, the BOINC client report the resources used by in-progress jobs; in this case, the max CPU jobs in progress is '''N*NCPUS''' and the max GPU jobs in progress is '''M*NGPUs'''. Otherwise, the overall maximum is '''N*NCPUS + M*NGPUS)'''.
+See the following section for a more powerful way of expressing limits on in-progress jobs.
 {{{
 <gpu_multiplier> GM </gpu_multiplier>
 }}}
+If your project uses GPUs, set this to roughly the ratio
+of GPU speed to CPU speed.
+Used in the calculation of job limits (see next 2 items).
+If your project uses GPUs, set this to roughly the ratio of GPU speed to CPU speed. Used in the calculation of job limits (see next 2 items).
 {{{
 <max_wus_to_send> N </max_wus_to_send>
 }}}
+Maximum jobs returned per scheduler RPC is '''N*(NCPUS + GM*NGPUS)'''.
+You can use this to limit the impact of faulty hosts.
+Default is 10.
+Maximum jobs returned per scheduler RPC is '''N*(NCPUS + GM*NGPUS)'''. You can use this to limit the impact of faulty hosts. Default is 10.
 {{{
 <max_ncpus>N</max_ncpus>
 }}}
 An upper bound on NCPUS (default: 16)
+An upper bound on NCPUS (default: 64)
 {{{
 <daily_result_quota> N </daily_result_quota>
 }}}
+Each host has a field MRD in the interval [1 .. daily_result_quota];
+it's initially daily_result_quota,
+and is adjusted as the host sends good or bad results.
+The maximum number of jobs sent to a given host in a 24-hour period is
+'''MRD*(NCPUS + GM*NGPUS)'''.
+You can use this to limit the impact of faulty hosts.
+Each host has a field MRD in the interval [1 .. daily_result_quota]; it's initially daily_result_quota, and is adjusted as the host sends good or bad results. The maximum number of jobs sent to a given host in a 24-hour period is '''MRD*(NCPUS + GM*NGPUS)'''. You can use this to limit the impact of faulty hosts.
 === Job limits (advanced) ===
+The following is a
+more adaptable way of expressing limits on the number of jobs in progress on a host.
+You can specify limits for specific apps, and for your projects as a whole.
+Within each of these, you can specify limits for CPU jobs, GPU jobs, or total.
+In the case of CPU and GPU jobs, you can specify whether the limit should be
+scaled by the number of devices present on the host.
+This uses a separate config file, '''config_aux.xml'''.
+The syntax is:
+The following is a more adaptable way of expressing limits on the number of jobs in progress on a host. You can specify limits for specific apps, and for your projects as a whole. Within each of these, you can specify limits for CPU jobs, GPU jobs, or total. In the case of CPU and GPU jobs, you can specify whether the limit should be scaled by the number of devices present on the host.
+This uses a separate config file, '''config_aux.xml'''. The syntax is:
 {{{
 <?xml version="1.0" ?>
 …
 </config>
 }}}
 === Job-cache scheduling ===
+This is the default.
+The feeder (a daemon program) maintains a cache of jobs in shared memory.
+Instances of the scheduler get jobs from this cache,
+reducing their database access overhead.
+This is the default. The feeder (a daemon program) maintains a cache of jobs in shared memory. Instances of the scheduler get jobs from this cache, reducing their database access overhead.
 {{{
 …
 }}}
 The size of the job cache.  Default is 100 jobs.
 {{{
 <feeder_query_size>N</feeder_query_size>
 …
 === Matchmaker scheduling ===
+This is a variant of job-cache scheduling.
+The job selection policy is determined by a "score function";
+this highest-scoring jobs are sent to the client.
+This is a variant of job-cache scheduling. The job selection policy is determined by a "score function"; this highest-scoring jobs are sent to the client.
 {{{
 …
 }}}
 If set, enable matchmaker scheduling.
 {{{
 <mm_min_slots>N</mm_min_slots>
 <mm_max_slots>N</mm_max_slots>
 }}}
 Specify the min and max number of jobs to scan for a given client request.
+Defaults are 20 and 50.
+Specify the min and max number of jobs to scan for a given client request. Defaults are 20 and 50.
 {{{
 <job_size_matching>0|1</job_size_matching>
 }}}
+If set, include a term in the score function that
+favors sending large jobs to fast hosts.
+To use this, you must run the census program as a periodic task
+to maintain statistics on the distribution of host speeds.
+If set, include a term in the score function that favors sending large jobs to fast hosts. To use this, you must run the census program as a periodic task to maintain statistics on the distribution of host speeds.
 === Accelerating retries ===
+The goal of this mechanism (which works with job-cache and matchmaker scheduling,
+but not locality scheduling) is to send timeout-generated retries to
+hosts that are likely to finish them fast.
+Here's how it works:
+The goal of this mechanism (which works with job-cache and matchmaker scheduling, but not locality scheduling) is to send timeout-generated retries to hosts that are likely to finish them fast. Here's how it works:
  * Hosts are deemed "reliable" (a slight misnomer) if they satisfy turnaround time and error rate criteria.
  * A job instance is deemed "need-reliable" if its priority is above a threshold.
+ * The scheduler tries to send need-reliable jobs to reliable hosts.
+   When it does, it reduces the delay bound of the job.
+ * When job replicas are created in response to errors or timeouts,
+   their priority is raised relative to the job's base priority.
+ * The scheduler tries to send need-reliable jobs to reliable hosts. When it does, it reduces the delay bound of the job.
+ * When job replicas are created in response to errors or timeouts, their priority is raised relative to the job's base priority.
 The configurable parameters are:
 {{{
 <reliable_on_priority>X</reliable_on_priority>
 }}}
+Results with priority at least '''reliable_on_priority''' are treated as "need-reliable".
+With matchmaker scheduling, they'll be sent preferentially to reliable hosts;
+with job-cache scheduling, they'll be sent ONLY to reliable hosts.
+Results with priority at least '''reliable_on_priority''' are treated as "need-reliable". With matchmaker scheduling, they'll be sent preferentially to reliable hosts; with job-cache scheduling, they'll be sent ONLY to reliable hosts.
 {{{
 …
 <reliable_max_error_rate>X</reliable_max_error_rate>
 }}}
+Hosts whose average turnaround is at most reliable_max_avg_turnaround
+and whose error rate is at most reliable_max_error_rate are considered 'reliable'.
+Make sure you set these low enough that a significant fraction (e.g. 25%) of your hosts qualify.
+Hosts whose average turnaround is at most reliable_max_avg_turnaround  and whose error rate is at most reliable_max_error_rate are considered 'reliable'. Make sure you set these low enough that a significant fraction (e.g. 25%) of your hosts qualify.
 {{{
 <reliable_reduced_delay_bound>X</reliable_reduced_delay_bound>
 }}}
 When a need-reliable result is sent to a reliable host,
+multiply the delay bound by '''reliable_reduced_delay_bound''' (typically 0.5 or so).
+When a need-reliable result is sent to a reliable host, multiply the delay bound by '''reliable_reduced_delay_bound''' (typically 0.5 or so).
 {{{
 <reliable_priority_on_over>X</reliable_priority_on_over>
 <reliable_priority_on_over_except_error>X</reliable_priority_on_over_except_error>
 }}}
+If '''reliable_priority_on_over''' is nonzero,
+increase the priority of duplicate jobs by that amount over the job's base priority.
+Otherwise, if '''reliable_priority_on_over_except_error''' is nonzero,
+increase the priority of duplicates caused by timeout (not error) by that amount.
+(Typically only one of these is nonzero, and is equal to '''reliable_on_priority'''.)
+NOTE: this mechanism can be used to preferentially send ANY job,
+not just retries, to fast/reliable hosts.
+To do so, set the workunit's priority to '''reliable_on_priority''' or greater.
+If '''reliable_priority_on_over''' is nonzero, increase the priority of duplicate jobs by that amount over the job's base priority. Otherwise, if '''reliable_priority_on_over_except_error''' is nonzero, increase the priority of duplicates caused by timeout (not error) by that amount. (Typically only one of these is nonzero, and is equal to '''reliable_on_priority'''.)
+NOTE: this mechanism can be used to preferentially send ANY job, not just retries, to fast/reliable hosts. To do so, set the workunit's priority to '''reliable_on_priority''' or greater.
 === Locality scheduling ===
 …
 <locality_scheduling/>
 }}}
+When possible, send work that uses the same files that the host already has.
+This is intended for projects which have large data files,
+where many different workunits use the same data file.
+In this case, to reduce download demands on the server,
+it may be advantageous to retain the data files on the hosts,
+and send them work for the files that they already have. See [LocalityScheduling Locality Scheduling].
+When possible, send work that uses the same files that the host already has. This is intended for projects which have large data files, where many different workunits use the same data file. In this case, to reduce download demands on the server, it may be advantageous to retain the data files on the hosts, and send them work for the files that they already have. See [wiki:LocalityScheduling Locality Scheduling].
 {{{
 <locality_scheduling_wait_period> N </locality_scheduling_wait_period>
 }}}
+This element only has an effect when used in conjunction with the previous locality scheduling element.
+It tells the scheduler to use 'trigger files' to inform the project
+that more work is needed for specific files.
+The period is the number of seconds which the scheduler will wait to see
+if the project can create additional work.
+Together with project-specific daemons or scripts this can be used for 'just-in-time' workunit creation.
+See [LocalityScheduling Locality Scheduling].
+This element only has an effect when used in conjunction with the previous locality scheduling element. It tells the scheduler to use 'trigger files' to inform the project that more work is needed for specific files. The period is the number of seconds which the scheduler will wait to see if the project can create additional work. Together with project-specific daemons or scripts this can be used for 'just-in-time' workunit creation. See [wiki:LocalityScheduling Locality Scheduling].
 === Job retransmission ===
 …
 <resend_lost_results> 0|1 </resend_lost_results>
 }}}
+If set, and a <other_results> list is present in scheduler request, resend any in-progress results not in the list.
+This is recommended; it may increase the efficiency of your project.
+For reasons that are not well understood, a BOINC client sometimes fails to receive the scheduler reply.
+This flag addresses that issue: it causes the SAME results to be resent by the scheduler,
+if the client has failed to receive them.
+Note: this will increase the load on your DB server; you can minimize this by creating an index:
+If set, and a <other_results> list is present in scheduler request, resend any in-progress results not in the list. This is recommended; it may increase the efficiency of your project. For reasons that are not well understood, a BOINC client sometimes fails to receive the scheduler reply. This flag addresses that issue: it causes the SAME results to be resent by the scheduler, if the client has failed to receive them. Note: this will increase the load on your DB server; you can minimize this by creating an index:
 {{{
 alter table result add index res_host_state (hostid, server_state);
 …
 <send_result_abort>0|1</send_result_abort>
 }}}
+If set, and the client is processing a result for a WU that has been canceled or is not in the DB
+(i.e. there's no chance of getting credit), tell the client to abort the result regardless of state.
+If client is processing a result for a WU that has been assimilated or is overdue
+(i.e. there's a chance of not getting credit) tell the client to abort the result if it hasn't started yet.
+Note: this will increase the load on your DB server.
+If set, and the client is processing a result for a WU that has been canceled or is not in the DB (i.e. there's no chance of getting credit), tell the client to abort the result regardless of state. If client is processing a result for a WU that has been assimilated or is overdue (i.e. there's a chance of not getting credit) tell the client to abort the result if it hasn't started yet. Note: this will increase the load on your DB server.
 === Data distribution ===
 …
 <replace_download_url_by_timezone>URL</replace_download_url_by_timezone>
 }}}
+OUTDATED: BERND, PLEASE UPDATE.
+When the scheduler sends work to hosts,
+it replaces the download URL appearing in the data and executable file descriptions
+with the download URL closest to the host's timezone.
+The project must provide a two-column file called 'download_servers' in the project root directory.
+This is a list of all download servers that will be inserted when work is sent to hosts.
+The first column is an integer listing the server's offset in seconds from UTC.
+The second column is the server URL in the format such as !http://einstein.phys.uwm.edu.
+The download servers must have identical file hierarchies and contents,
+and the path to file and executables must start with '/download/...'
+as in '!http://X/download/123/some_file_name'.
+OUTDATED: BERND, PLEASE UPDATE. When the scheduler sends work to hosts, it replaces the download URL appearing in the data and executable file descriptions with the download URL closest to the host's timezone. The project must provide a two-column file called 'download_servers' in the project root directory. This is a list of all download servers that will be inserted when work is sent to hosts. The first column is an integer listing the server's offset in seconds from UTC. The second column is the server URL in the format such as !http://einstein.phys.uwm.edu. The download servers must have identical file hierarchies and contents, and the path to file and executables must start with '/download/...' as in '!http://X/download/123/some_file_name'.
 {{{
 <cache_md5_info> 0|1 </cache_md5_info>
 }}}
+When creating work, keep a record (in files called foo.md5) of the file length
+and md5 sum of data files and executables.
+This can greatly reduce the time needed to create work,
+if (1) these files are re-used, and (2) there are many of these files,
+and (3) reading the files from disk is time-consuming.
+When creating work, keep a record (in files called foo.md5) of the file length and md5 sum of data files and executables. This can greatly reduce the time needed to create work, if (1) these files are re-used, and (2) there are many of these files, and (3) reading the files from disk is time-consuming.
 === Logging ===
 The contents of the scheduler log file is controlled by the following:
 …
 <debug_assignment/>
 }}}
+Explain the sending of [AssignedWork assigned work].
+Explain the sending of [wiki:AssignedWork assigned work].
 {{{
 <debug_edf_sim_detail/>
 }}}
 Show the details of EDF simulation
 {{{
 <debug_edf_sim_workload/>
 }}}
 Show the initial conditions of EDF simulation
 {{{
 <debug_handle_results/>
 }}}
 Show the handling of reported jobs.
 {{{
 <debug_locality>
 }}}
 Show locality scheduling debugging info.
 {{{
 <debug_prefs/>
 }}}
 Show the propagation of global prefs.
 {{{
 <debug_quota/>
 }}}
 Show info related to job quotas (per RPC, max in progress, max per day)
 {{{
 <debug_request_details/>
 }}}
 Show details of request message.
 {{{
 <debug_request_headers/>
 }}}
 Show HTTP request headers.
 {{{
 <debug_send/>
 }}}
 Explain the sending of jobs.
 {{{
 <debug_user_messages/>
 }}}
 Show messages we're sending to the user.
 {{{
 <debug_version_select/>
 …
 The overall verbosity is controlled by the following:
 {{{
 <sched_debug_level> N </sched_debug_level>
 }}}
+Log messages have a "level": 1=minimal, 2=normal, 3=debug.
+The messages enabled by the above flags have level=2.
+If you set this option to N, only messages of level N or less will be written.
+Log messages have a "level": 1=minimal, 2=normal, 3=debug. The messages enabled by the above flags have level=2. If you set this option to N, only messages of level N or less will be written.
 === Client control === #client-control
 …
 <next_rpc_delay>x</next_rpc_delay>
 }}}
+In each scheduler reply, tell the clients to do another scheduler RPC after at most X seconds,
+regardless of whether they need work.
+This is useful, e.g., to ensure that in-progress jobs can be canceled in a bounded amount of time.
+In each scheduler reply, tell the clients to do another scheduler RPC after at most X seconds, regardless of whether they need work. This is useful, e.g., to ensure that in-progress jobs can be canceled in a bounded amount of time.
 {{{
 <verify_files_on_app_start/>
 }}}
+Before starting or restarting an app,
+check contents of input files and app version files by either MD5 or digital signature check.
+Detects user tampering with file
+(but doesn't really increase security, since user could also change MD5s or signatures in client state file).
+Before starting or restarting an app, check contents of input files and app version files by either MD5 or digital signature check. Detects user tampering with file (but doesn't really increase security, since user could also change MD5s or signatures in client state file).
 {{{
 <symstore>URL</symstore>
 }}}
 URL of your project's symbol store, used for debugging Windows applications.
 {{{
 <min_core_client_version_announced> N </min_core_client_version_announced>
 }}}
+Announce a new version of the BOINC core client,
+which in the future will be the minimum required version.
+In conjunction with the next tag,
+you can warn users with version below this to upgrade by a specified deadline.
+The version number is encoded as 10000*major + 100*minor + release.
+Announce a new version of the BOINC core client, which in the future will be the minimum required version. In conjunction with the next tag, you can warn users with version below this to upgrade by a specified deadline. The version number is encoded as 10000*major + 100*minor + release.
 {{{
 <min_core_client_upgrade_deadline> N </min_core_client_upgrade_deadline>
 }}}
+Use in conjunction with the previous tag.
+The value given here is the Unix epoch returned by time(2) until which hosts can update their core client.
+After this time, they may be shut out of the project.
+Before this time, they will receive messages warning them to upgrade.
+Use in conjunction with the previous tag. The value given here is the Unix epoch returned by time(2) until which hosts can update their core client. After this time, they may be shut out of the project. Before this time, they will receive messages warning them to upgrade.
 {{{
 <msg_to_host/>
 }}}
 If present, check the msg_to_host table on each RPC, and send the client any messages queued for it.
 {{{
 <non_cpu_intensive> 0|1 </non_cpu_intensive>
 …
  * The client will download one result at a time.
+ * This result will be executed whenever computation is enabled (bypassing the normal scheduling mechanism).
+This is intended for [NonCpuIntensive applications that use little CPU time],
+e.g. that do network or host measurements.
+ * This result will be executed whenever computation is enabled (bypassing the normal scheduling mechanism).
+This is intended for [wiki:NonCpuIntensive applications that use little CPU time], e.g. that do network or host measurements.
 === Deprecated options ===
 {{{
 <no_amd_k6>1</no_amd_k6>
 }}}
 Don't issue work to clients with AMD K6 processors.  Equivalent to
 {{{
 <ban_cpu>.*AMD.*\t.*Family 5 Model 8 Stepping 0.*</ban_cpu>
 }}}
 == Upload certificates ==
 {{{
 <dont_generate_upload_certificates/>
 }}}
+Don't put upload certificates in results.
+This makes result generation a lot faster,
+since no encryption is done, but you lose protection against DoS attacks on your upload servers.
+Don't put upload certificates in results. This makes result generation a lot faster, since no encryption is done, but you lose protection against DoS attacks on your upload servers.
 {{{
 <ignore_upload_certificates/>
 }}}
+If upload certificates are not generated,
+this option must be enabled to force the file upload handler to accept files.
+If upload certificates are not generated, this option must be enabled to force the file upload handler to accept files.
 == Default preferences ==
 …
 <default_disk_max_used_gb> X </default_disk_max_used_gb>
 }}}
+Sets the default value for the `disk_max_used_gb` preference so it's consistent
+between the scheduler and web pages.
+The scheduler uses it when a request for work doesn't include preferences,
+or the preference is set to zero.
+The web page scripts use it to set the initial value when displaying or editing preferences the first time,
+or when the user never saved them.
+Default is 100.
+Sets the default value for the `disk_max_used_gb` preference so it's consistent between the scheduler and web pages. The scheduler uses it when a request for work doesn't include preferences, or the preference is set to zero. The web page scripts use it to set the initial value when displaying or editing preferences the first time, or when the user never saved them. Default is 100.
 {{{
 <default_disk_max_used_pct> X </default_disk_max_used_pct>
 }}}
+Sets the default value for the `disk_max_used_pct` preference so its consistent
+between the scheduler and web pages.
+The scheduler uses it when a request for work doesn't include preferences,
+or the preference is set to zero.
+The web page scripts use it to set the initial value when displaying
+or editing preferences the first time,
+or when the user never saved them. Default is 50.
+Sets the default value for the `disk_max_used_pct` preference so its consistent between the scheduler and web pages. The scheduler uses it when a request for work doesn't include preferences, or the preference is set to zero. The web page scripts use it to set the initial value when displaying or editing preferences the first time, or when the user never saved them. Default is 50.
 {{{
 <default_disk_min_free_gb> X </default_disk_min_free_gb>
 }}}
+Sets the default value for the `disk_min_free_gb` preference so its consistent
+between the scheduler and web pages.
+The scheduler uses it when a request for work doesn't include preferences.
+The web page scripts use it to set the initial value when displaying or editing preferences the first time,
+or when the user never saved them.
+Also, the scheduler uses this setting to override any smaller preference from the host,
+it enforces a 'minimum free disk space' to keep from filling up the drive.
+Recommend setting this no smaller than .001 (1MB or 1,000,000 bytes). Default is .001.
+Sets the default value for the `disk_min_free_gb` preference so its consistent between the scheduler and web pages. The scheduler uses it when a request for work doesn't include preferences. The web page scripts use it to set the initial value when displaying or editing preferences the first time, or when the user never saved them. Also, the scheduler uses this setting to override any smaller preference from the host, it enforces a 'minimum free disk space' to keep from filling up the drive. Recommend setting this no smaller than .001 (1MB or 1,000,000 bytes). Default is .001.
 == Credit ==
+(See also the command-line options of the [ValidationIntro validator]).
+(See also the command-line options of the [wiki:ValidationIntro validator]).
 {{{
 <granted_credit_weight>X</granted_credit_weight>
 …
 <fp_benchmark_weight> X </fp_benchmark_weight>
 }}}
+The weighting given to the Whetstone benchmark in the calculation of claimed credit.
+Must be in [0 .. 1]. Projects whose applications are floating-point intensive should use 1; pure integer applications, 0.
+Choosing an appropriate value will reduce the disparity in claimed credit between hosts.
+The script html/ops/credit_study.php, run against the database of a running project, will suggest what value to use.
+The weighting given to the Whetstone benchmark in the calculation of claimed credit. Must be in [0 .. 1]. Projects whose applications are floating-point intensive should use 1; pure integer applications, 0. Choosing an appropriate value will reduce the disparity in claimed credit between hosts. The script html/ops/credit_study.php, run against the database of a running project, will suggest what value to use.
 {{{
 <granted_credit_weight>X</granted_credit_weight>
 …
 <delete_delay_hours>X</delete_delay_hours>
 }}}
 Wait X hours before deleting files.
+This provides a 'grace period' during which late results will still get credit.
+Wait X hours before deleting files. This provides a 'grace period' during which late results will still get credit.
 {{{
 <httpd_user>username</httpd_user>
 }}}
+The user name under which the web server runs.
+As a safeguard, the file deleter skips files not owned by this user.
+The user name under which the web server runs. As a safeguard, the file deleter skips files not owned by this user.
 == Server status page options == #server-status
 …
 }}}
 Host name of web server.
 {{{
 <sched_host>hostname</sched_host>
 }}}
 Host name of scheduling server.
 {{{
 <uldl_host>hostname</uldl_host>
 }}}
 Host name of upload/download server.
 {{{
 <uldl_pid>path</uldl_pid>
 }}}
 pid file of upload/download server (default: `/etc/httpd/run/httpd.pid`).
 {{{
 <ssh_exe>path</ssh_exe>
 }}}
 path to `ssh` (default: `/usr/bin/ssh`).
 {{{
 <ps_exe>path</ps_exe>
 …
 path to `ps` (which supports "w" flag) (default: `/bin/ps`).
 == Web site features == #website
 {{{
 …
 }}}
 If present, don't show profile pictures until they've been screened and approved by project admins.
 {{{
 <show_results/>
 }}}
 Enable web site features that show results (per user, host, etc.).
 {{{
 <dont_suppress_pending/>
 }}}
 Do not hide incomplete results when using adaptive replication.
 {{{
 <no_forum_rating/>
 }}}
 Disable forum post rating.
 {{{
 <no_web_account_creation/>
 }}}
 Don't allow account creation via the web.
 {{{
 <akismet_key> 1234567890ab </akismet_key>
 }}}
 If set, akismet.com is used to check post contents to protect forums from spam.
+See [ProtectionFromSpam Protecting message boards from spam] for more information.
+If set, akismet.com is used to check post contents to protect forums from spam. See [wiki:ProtectionFromSpam Protecting message boards from spam] for more information.
 {{{
 <users_per_page>N</users_per_page>
 }}}
 Number of entries per page for top users/teams/hosts.  Default is 20.
 {{{
 <teams_per_page>N</teams_per_page>
 …
 <recaptcha_private_key>X</recaptcha_private_key>
 }}}
 Enable the use of Recaptcha for profile creation/editing;
+see [ProtectionFromSpam Protecting message boards from spam] for more information.
+Enable the use of Recaptcha for profile creation/editing; see [wiki:ProtectionFromSpam Protecting message boards from spam] for more information.
 {{{
 <profile_min_credit>X</profile_min_credit>
 }}}
 The minimum amount of credit to create or edit a profile.
 {{{
 <team_forums_members_only>0|1</team_forums_members_only>
 }}}
 If set, team message boards are visible only to team members.
 {{{
 <moderators_vote_to_ban>0|1</moderators_vote_to_ban>
 }}}
 If set, banishments require a majority vote among moderators.
 {{{
 <no_computing>0|1</no_computing>
 }}}
+If set, web pages have no references to computing (tasks, credit etc.).
+For projects that are using Bossa or Bolt.
+If set, web pages have no references to computing (tasks, credit etc.). For projects that are using Bossa or Bolt.
 == Miscellaneous == #misc
 …
 <min_core_client_version> N </min_core_client_version>
 }}}
+If the scheduler gets a request from a client with a version number less than this,
+it returns an error message and doesn't do any other processing.
+The version number is expressed as an integer with the encoding 10000*major + 100*minor + release.
+You can also specify this separately for each [AppVersion application].
+If the scheduler gets a request from a client with a version number less than this, it returns an error message and doesn't do any other processing. The version number is expressed as an integer with the encoding 10000*major + 100*minor + release. You can also specify this separately for each [wiki:AppVersion application].
 {{{
 <ended>0|1</ended>
 }}}
 Project has permanently ended.  Tell clients so user can be notified.
 {{{
 <disable_account_creation/>
 }}}
 If present, disallow account creation.
 {{{
 <min_passwd_length> N </min_passwd_length>
 }}}
 Minimum length of user passwords. Default is 6.
 {{{
 <request_time_stats_log/>
 }}}
+If present, the scheduler will tell clients (via scheduler replies) to
+upload (via scheduler requests) their time stats log
+(which contains records of when the client started and stopped running).
+If present, the scheduler will tell clients (via scheduler replies) to upload (via scheduler requests) their time stats log (which contains records of when the client started and stopped running).
 {{{
 <fuh_debug_level> N </fuh_debug_level>
 }}}
 Verbosity level for file upload handler log output. 1=minimal, 2=normal (default), 3=verbose.
 {{{
 <dont_store_success_stderr/>
 }}}
+If present, don't store the stderr log in the database for successful workunits.
+May be useful to save on database size. Available since r18528.
+If present, don't store the stderr log in the database for successful workunits. May be useful to save on database size. Available since r18528.
 == Database info == #db
 …
 [ <replica_db_passwd>database_password</replica_db_passwd> ]
 }}}
+Description a replica database server, which is used for read-only queries (optional).
+NOTE: according to Bernd Machenschalk,
+using a separate user account with read-only access to the replica
+increases the apparent consistency between main and replica.
+Description a replica database server, which is used for read-only queries (optional). NOTE: according to Bernd Machenschalk, using a separate user account with read-only access to the replica increases the apparent consistency between main and replica.
 == Hosts, directories, and URLs == #dirs
+(These are created by [MakeProject make_project]; normally you don't need to change them.)
+(These are created by [wiki:MakeProject make_project]; normally you don't need to change them.)
 {{{
 <master_url>URL</master_url>
 …
 <host>hostname</host>
 }}}
+name of project's main host, as given by Python's `socket.hostname()`.
+Daemons and tasks run on this host by default.
+name of project's main host, as given by Python's `socket.hostname()`. Daemons and tasks run on this host by default.
 {{{
 …
 }}}
 ID of scheduler shared memory. Must be unique on host.
 {{{
 <download_url>URL</download_url>
 }}}
 URL of data server for download.
 {{{
 <download_dir>path</download_dir>
 }}}
 absolute path of download directory.
 {{{
 <uldl_dir_fanout>N</uldl_dir_fanout>
 }}}
 fan-out factor of upload and download directories
+(see [DirHierarchy Hierarchical upload/download directories]).
+fan-out factor of upload and download directories (see [wiki:DirHierarchy Hierarchical upload/download directories]).
 {{{
 <upload_url>URL</upload_url>
 }}}
 URL of file upload handler.
 {{{
 <upload_dir>path</upload_dir>
 }}}
 absolute path of upload directory.
 {{{
 <cgi_url>URL</cgi_url>
 }}}
 URL of scheduler.
 {{{
 <log_dir>path</log_dir>
 }}}
 absolute path of logfile directory.
 {{{
 <bin_dir>relative-path</bin_dir>      <!-- relative to project_dir -->
 …
 <sched_lockfile_dir>path</sched_lockfile_dir>
 }}}
+Enables scheduler locking (recommended) and specifies directory where scheduler lockfiles are stored.
+Must be writable to the Apache user.
+Enables scheduler locking (recommended) and specifies directory where scheduler lockfiles are stored. Must be writable to the Apache user.
 = Parsing project options = #parsing-config
 A program or script can access project options as follows:
 …
  * PHP: use the get_config() and parse_config() functions in inc/util.inc
  * scripts: use the bin/parse_config program