From: Jeff Layton Date: Wed, 11 Aug 2021 12:08:32 +0000 (-0400) Subject: doc: document that NEARFULL conditions can result in slow writes X-Git-Tag: v17.1.0~1104^2 X-Git-Url: http://git-server-git.apps.pok.os.sepia.ceph.com/?a=commitdiff_plain;h=6327a8d740daf40a21b2c77dba0d626ea9b1f373;p=ceph.git doc: document that NEARFULL conditions can result in slow writes The change to doing sync I/Os when we're in NEARFULL conditions apparently caught some folks by surprise. Add something to clarify that to the kclient debugging docs. Also, remove the incomplete sentence that follows it, which contains no useful information. Fixes: https://tracker.ceph.com/issues/49406 Signed-off-by: Jeff Layton --- diff --git a/doc/cephfs/troubleshooting.rst b/doc/cephfs/troubleshooting.rst index 78ad18ddeb4..ea33019f043 100644 --- a/doc/cephfs/troubleshooting.rst +++ b/doc/cephfs/troubleshooting.rst @@ -124,8 +124,8 @@ slow requests are probably the ``mdsc`` and ``osdc`` files. * osdc: Dumps the current ops in-flight to OSDs (ie, file data IO) * osdmap: Dumps the current OSDMap epoch, pools, and OSDs -If there are no stuck requests but you have file IO which is not progressing, -you might have a... +If the data pool is in a NEARFULL condition, then the kernel cephfs client +will switch to doing writes synchronously, which is quite slow. Disconnected+Remounted FS =========================