multipathd: deterministic io throughput in multipath
authorMuneendra Kumar M <mmandala@Brocade.com>
Mon, 6 Feb 2017 06:21:37 +0000 (06:21 +0000)
committerChristophe Varoqui <christophe.varoqui@opensvc.com>
Fri, 10 Feb 2017 08:52:24 +0000 (09:52 +0100)
commitc3705a12b893cc302a89587c4d37d120952eeebb
tree5cea722289e11a4150dca52725dcad3889ddf675
parenta458a2666a44e75bbbf33705d6749a4e44e6e4df
multipathd: deterministic io throughput in multipath

This patch adds three configuration parameters, "san_path_err_threshold",
"san_path_err_recovery_time" and "san_path_err_forget_rate".
multipathd will watch paths and check how many times a path has been failed due
to errors.If the number of failures on a particular path is greater then the
san_path_err_threshold then the path will not  reinstante till
san_path_err_recovery_time.These path failures should occur within a
san_path_err_forget_rate checks, if not we will consider the path is good enough
to reinstate.If it is the only available path, it will immediately be
reintegrated.

This helps us to place the path in failed state if we hit lot of errors on a particular path
due to network /target issues and allow the admin to rectify the errors on a path.

Signed-off-by: M Muneendra Kumar <mmandala@brocade.com>
libmultipath/config.c
libmultipath/config.h
libmultipath/configure.c
libmultipath/defaults.h
libmultipath/dict.c
libmultipath/dict.h
libmultipath/propsel.c
libmultipath/propsel.h
libmultipath/structs.h
multipath/multipath.conf.5
multipathd/main.c