Merge branch 'thehyve/fix-crunch-documentation' Fix a typo in Crunch Dispatch install...

[arvados.git] / doc / install / crunch2-slurm / install-dispatch.html.textile.liquid

diff --git a/doc/install/crunch2-slurm/install-dispatch.html.textile.liquid b/doc/install/crunch2-slurm/install-dispatch.html.textile.liquid
index 27f15b103e10e12cdb7a83ec7f0bb3ee6e9e138f..1313ac190d8f9a9884786dbe0ea3a85dafceb409 100644 (file)
--- a/doc/install/crunch2-slurm/install-dispatch.html.textile.liquid
+++ b/doc/install/crunch2-slurm/install-dispatch.html.textile.liquid
@@ -48,7 +48,7 @@ Set up crunch-dispatch-slurm's configuration directory:
 
 <notextile>
 <pre><code>~$ <span class="userinput">sudo mkdir -p /etc/arvados</span>
-~$ <span class="userinput">sudo install -d -o -root -g <b>crunch</b> -m 0750 /etc/arvados/crunch-dispatch-slurm</span>
+~$ <span class="userinput">sudo install -d -o root -g <b>crunch</b> -m 0750 /etc/arvados/crunch-dispatch-slurm</span>
 </code></pre>
 </notextile>
 
@@ -69,8 +69,8 @@ Override Keep service discovery with a predefined list of Keep URIs. This can be
 
 <notextile>
 <pre><code class="userinput">Client:
-  APIHost: <b>zzzzz.arvadosapi.com</b>
-  AuthToken: <b>zzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzz</b>
+  APIHost: zzzzz.arvadosapi.com
+  AuthToken: zzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzz
   KeepServiceURIs:
   - <b>http://127.0.0.1:25107</b>
 </code></pre>
@@ -81,22 +81,32 @@ h3. PollPeriod
 crunch-dispatch-slurm polls the API server periodically for new containers to run.  The @PollPeriod@ option controls how often this poll happens.  Set this to a string of numbers suffixed with one of the time units @ns@, @us@, @ms@, @s@, @m@, or @h@.  For example:
 
 <notextile>
-<pre><code class="userinput">Client:
-  APIHost: <b>zzzzz.arvadosapi.com</b>
-  AuthToken: <b>zzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzz</b>
-PollPeriod: <b>3m30s</b>
+<pre><code class="userinput">PollPeriod: <b>3m30s</b>
 </code></pre>
 </notextile>
 
+h3. PrioritySpread
+
+crunch-dispatch-slurm adjusts the "nice" values of its SLURM jobs to ensure containers are prioritized correctly relative to one another. This option tunes the adjustment mechanism.
+* If non-Arvados jobs run on your SLURM cluster, and your Arvados containers are waiting too long in the SLURM queue because their "nice" values are too high for them to compete with other SLURM jobs, you should use a smaller PrioritySpread value.
+* If you have an older SLURM system that limits nice values to 10000, a smaller @PrioritySpread@ can help avoid reaching that limit.
+* In other cases, a larger value is beneficial because it reduces the total number of adjustments made by executing @scontrol@.
+
+The smallest usable value is @1@. The default value of @10@ is used if this option is zero or negative. Example:
+
+<notextile>
+<pre><code class="userinput">PrioritySpread: <b>1000</b>
+</code></pre>
+</notextile>
+
+
+
 h3. SbatchArguments
 
 When crunch-dispatch-slurm invokes @sbatch@, you can add switches to the command by specifying @SbatchArguments@.  You can use this to send the jobs to specific cluster partitions or add resource requests.  Set @SbatchArguments@ to an array of strings.  For example:
 
 <notextile>
-<pre><code class="userinput">Client:
-  APIHost: <b>zzzzz.arvadosapi.com</b>
-  AuthToken: <b>zzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzz</b>
-SbatchArguments:
+<pre><code class="userinput">SbatchArguments:
 - <b>"--partition=PartitionName"</b>
 </code></pre>
 </notextile>
@@ -106,10 +116,7 @@ h3. CrunchRunCommand: Dispatch to SLURM cgroups
 If your SLURM cluster uses the @task/cgroup@ TaskPlugin, you can configure Crunch's Docker containers to be dispatched inside SLURM's cgroups.  This provides consistent enforcement of resource constraints.  To do this, use a crunch-dispatch-slurm configuration like the following:
 
 <notextile>
-<pre><code class="userinput">Client:
-  APIHost: <b>zzzzz.arvadosapi.com</b>
-  AuthToken: <b>zzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzz</b>
-CrunchRunCommand:
+<pre><code class="userinput">CrunchRunCommand:
 - <b>crunch-run</b>
 - <b>"-cgroup-parent-subsystem=memory"</b>
 </code></pre>
@@ -130,10 +137,7 @@ h3. CrunchRunCommand: Using host networking for containers
 Older Linux kernels (prior to 3.18) have bugs in network namespace handling which can lead to compute node lockups.  This by is indicated by blocked kernel tasks in "Workqueue: netns cleanup_net".   If you are experiencing this problem, as a workaround you can disable use of network namespaces by Docker across the cluster.  Be aware this reduces container isolation, which may be a security risk.
 
 <notextile>
-<pre><code class="userinput">Client:
-  APIHost: <b>zzzzz.arvadosapi.com</b>
-  AuthToken: <b>zzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzz</b>
-CrunchRunCommand:
+<pre><code class="userinput">CrunchRunCommand:
 - <b>crunch-run</b>
 - <b>"-container-enable-networking=always"</b>
 - <b>"-container-network-mode=host"</b>
@@ -145,10 +149,7 @@ h3. MinRetryPeriod: Rate-limit repeated attempts to start containers
 If SLURM is unable to run a container, the dispatcher will submit it again after the next PollPeriod. If PollPeriod is very short, this can be excessive. If MinRetryPeriod is set, the dispatcher will avoid submitting the same container to SLURM more than once in the given time span.
 
 <notextile>
-<pre><code class="userinput">Client:
-  APIHost: <b>zzzzz.arvadosapi.com</b>
-  AuthToken: <b>zzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzz</b>
-MinRetryPeriod: <b>30s</b>
+<pre><code class="userinput">MinRetryPeriod: <b>30s</b>
 </code></pre>
 </notextile>