X-Git-Url: https://git.octo.it/?p=collectd.git;a=blobdiff_plain;f=docs%2FBUILD.dpdkstat.md;h=457fc0fa30bcafb9012db9c62767591cd58d88c0;hp=fe9f0e68acc292363a476ec8dc4fdc96ba038017;hb=7111bb6df7628edce3a8e538b386fbe27633a191;hpb=c3d354c58d56c4b2bb4138a227f3546928bd84f2

diff --git a/docs/BUILD.dpdkstat.md b/docs/BUILD.dpdkstat.md
index fe9f0e68..457fc0fa 100644
--- a/docs/BUILD.dpdkstat.md
+++ b/docs/BUILD.dpdkstat.md
@@ -1,7 +1,17 @@
 # The dpdkstat plugin
 
+This plugin is optional and only has a specific use case: monitoring DPDK applications
+that don't expose stats in any other way than the DPDK xstats API.
+
 **Data Plane Development Kit** (DPDK) is a set of drivers and libraries for fast
-packet processing.
+packet processing. Please note that this plugin is a polling based plugin rather
+than an events based plugin (using it will drive up core utilization on a system).
+
+**PLEASE DO NOT USE THIS PLUGIN FOR OVS-DPDK**. dpdkstat is really for DPDK
+applications that have no other way of exposing stats. For OVS or OVS-with-DPDK the
+Open vSwitch plugins available in collectd 5.8.0 should be used for
+collecting stats and events. In addition the OVS plugin is events based rather
+than polling based and will have a smaller footprint on the system.
 
 ## Summary
 
@@ -208,6 +218,12 @@ See also: http://dpdk.org/doc/guides/prog_guide/multi_proc_support.html
  *  The same PCI device configuration should be passed to the primary process as
     the secondary process uses the same port indexes as the primary.
  *  A blacklist / whitelist of NICs isn't supported yet.
+ *  Plugin initialization time depends on read interval. It requires 5 read
+    cycles to set up internal buffers and states. During that time no statistics
+    are submitted.
+ *  If number of DPDK ports is increased while plugin is running, internal
+    buffers are resized. That requires 3 read cycles and no port statistics
+    are submitted in that time.
 
 ## License