Doc: Resolve !499 by documenting Slurm option --switches

doc.zih.tu-dresden.de/docs/jobs_and_resources/slurm.md

@@ -132,6 +132,7 @@ resource requirements and control communication.
     | `-a, --array=<arg>`        | Submit an array job ([examples](slurm_examples.md#array-jobs)) |
     | `-w <node1>,<node2>,...`   | Restrict job to run on specific nodes only |
     | `-x <node1>,<node2>,...`   | Exclude specific nodes from job |
+    | `--switches=<count>[@max-time]` | Optimum switches and max time to wait for optimum |
     | `--test-only`              | Retrieve estimated start time of a job considering the job queue; does not actually submit the job nor run the application |
 
 !!! note "Output and Error Files"
@@ -152,6 +153,16 @@ If you want to place your job onto specific nodes, there are two options for doi
 `-p, --partition=<name>` to specify a host group aka. [partition](partitions_and_limits.md) that fits
 your needs. Or, use `-w, --nodelist=<host1,host2,..>` with a list of hosts that will work for you.
 
+### Number of Switches
+
+You can fine tune your job by specifying the number of switches desired for the job allocation and
+optionally the maximum time to wait for that number of switches. The corresponding option to
+`sbatch` is `--switches=<count>[@max-time]`. The job remains pending until it either finds an
+allocation with desired switch count or the time limit expires. Acceptable time formats include
+"minutes", "minutes:seconds", "hours:minutes:seconds", "days-hours", "days-hours:minutes" and
+"days-hours:minutes:seconds". For a detailed explanation, please refer to the
+[sbatch online documentation](https://slurm.schedmd.com/sbatch.html#OPT_switches).
+
 ## Interactive Jobs
 
 Interactive activities like editing, compiling, preparing experiments etc. are normally limited to