performance

Server-Diagnostics---Troubleshooting.md

@@ -152,3 +152,25 @@ Successful result:
         <displayname>Feiertage Bayern</displayname>
         <C:calendar-description>Feiertage Bayern</C:calendar-description>
 ```
+
+# Performance Issues
+
+## CPU+Disk performance issues
+
+(i) supported since 3.3.2
+
+In case collections with higher amount of items it can be that PROPFIND and REPORT requests are slow and even PUT requests take some time. In this case consider change of caching method.
+
+Precondition: file system supports mtime with ns proper (us is potentially also still enough, ms can turn risky)
+
+Enable by configuring `[storage] use_mtime_and_size_for_item_cache = True`
+
+## Network filesystem performance issues
+
+(i) supported since 3.3.2
+
+In case collections are stored on a network filesystem, e.g. NFS or GlusterFS it can make sense to keep the cache on local node.
+
+Check following options
+* `[storage] filesystem_cache_folder = /path/to/local/filesystem`
+* `[storage] use_cache_subfolder_for_item = True`