From: Zac Dover Date: Tue, 12 Aug 2025 06:46:12 +0000 (+1000) Subject: doc/cephfs: edit troubleshooting.rst X-Git-Tag: testing/wip-jcollin-testing-20250820.041311-squid~10^2 X-Git-Url: http://git-server-git.apps.pok.os.sepia.ceph.com/?a=commitdiff_plain;h=56ffdf8b6a346035df2d6b427ab56339dcca03ff;p=ceph-ci.git doc/cephfs: edit troubleshooting.rst Edit the "Dynamic Debugging" section of doc/cephfs/troubleshooting.rst. Signed-off-by: Zac Dover doc/cephfs: improve dynamic debugging section Signed-off-by: Venky Shankar (cherry picked from commit a15653a2fbb385aae4cfa5245728b3e14e705bfe) --- diff --git a/doc/cephfs/troubleshooting.rst b/doc/cephfs/troubleshooting.rst index 66927eb3fa9..32ebc73b00b 100644 --- a/doc/cephfs/troubleshooting.rst +++ b/doc/cephfs/troubleshooting.rst @@ -374,9 +374,29 @@ and then reinstall it so that you have the latest version. Dynamic Debugging ================= -You can enable dynamic debug against the CephFS module. +Dynamic debugging for CephFS kernel driver allows to enable or disable debug +logging. The kernel driver logs are written to the kernel ring buffer and can +be examined using ``dmesg(1)`` utility. Debug logging is disabled by default +because enabling debug logging can result in system slowness and a drop in I/O +throughput. -Please see: https://github.com/ceph/ceph/blob/master/src/script/kcon_all.sh +Enable dynamic debug against the CephFS module. + +See: https://github.com/ceph/ceph/blob/master/src/script/kcon_all.sh + +Note: Running the above script enables debug logging for the CephFS kernel +driver, libceph, and the kernel RBD module. To enable debug logging for a +specific component (for example, for the CephFS kernel driver), run a command of the following form: + +.. prompt:: bash # + + echo 'module ceph +p' > /sys/kernel/debug/dynamic_debug/control + +To disable debug logging, run a command of the following form: + +.. prompt:: bash # + + echo 'module ceph -p' > /sys/kernel/debug/dynamic_debug/control In-memory Log Dump ==================