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---
libmultipath/dict.c | 2 +-
multipath.conf.annotated | 4 ++--
multipath.conf.defaults | 2 +-
multipath.conf.synthetic | 2 +-
multipath/multipath.conf.5 | 18 +++++++++++++++---
5 files changed, 20 insertions(+), 8 deletions(-)
Index: multipath-tools/libmultipath/dict.c
===================================================================
--- multipath-tools.orig/libmultipath/dict.c
+++ multipath-tools/libmultipath/dict.c
@@ -2181,7 +2181,7 @@ init_keywords(void)
install_keyword("polling_interval", &polling_interval_handler, &snprint_def_polling_interval);
install_keyword("udev_dir", &udev_dir_handler, &snprint_def_udev_dir);
install_keyword("multipath_dir", &multipath_dir_handler, &snprint_def_multipath_dir);
- install_keyword("selector", &def_selector_handler, &snprint_def_selector);
+ install_keyword("path_selector", &def_selector_handler, &snprint_def_selector);
install_keyword("path_grouping_policy", &def_pgpolicy_handler, &snprint_def_path_grouping_policy);
install_keyword("getuid_callout", &def_getuid_callout_handler, &snprint_def_getuid_callout);
install_keyword("prio", &def_prio_handler, &snprint_def_prio);
Index: multipath-tools/multipath.conf.annotated
===================================================================
--- multipath-tools.orig/multipath.conf.annotated
+++ multipath-tools/multipath.conf.annotated
@@ -27,14 +27,14 @@
# polling_interval 10
#
# #
-# # name : selector
+# # name : path_selector
# # scope : multipath
# # desc : the default path selector algorithm to use
# # these algorithms are offered by the kernel multipath target
# # values : "round-robin 0"
# # default : "round-robin 0"
# #
-# selector "round-robin 0"
+# path_selector "round-robin 0"
#
# #
# # name : path_grouping_policy
Index: multipath-tools/multipath.conf.defaults
===================================================================
--- multipath-tools.orig/multipath.conf.defaults
+++ multipath-tools/multipath.conf.defaults
@@ -4,7 +4,7 @@
#defaults {
# udev_dir /dev
# polling_interval 5
-# selector "round-robin 0"
+# path_selector "round-robin 0"
# path_grouping_policy failover
# getuid_callout "/lib/udev/scsi_id --whitelisted --device=/dev/%n"
# prio const
Index: multipath-tools/multipath.conf.synthetic
===================================================================
--- multipath-tools.orig/multipath.conf.synthetic
+++ multipath-tools/multipath.conf.synthetic
@@ -5,7 +5,7 @@
#defaults {
# udev_dir /dev
# polling_interval 10
-# selector "round-robin 0"
+# path_selector "round-robin 0"
# path_grouping_policy multibus
# getuid_callout "/lib/udev/scsi_id --whitelisted --device=/dev/%n"
# prio const
Index: multipath-tools/multipath/multipath.conf.5
===================================================================
--- multipath-tools.orig/multipath/multipath.conf.5
+++ multipath-tools/multipath/multipath.conf.5
@@ -81,10 +81,22 @@ default verbosity. Higher values increas
levels are between 0 and 6; default is
.I 2
.TP
-.B selector
+.B path_selector
The default path selector algorithm to use; they are offered by the
-kernel multipath target. The only currently implemented is
-.I "round-robin 0"
+kernel multipath target. There are three selector algorithms.
+.RS
+.TP 12
+.B "round-robin 0"
+Loop through every path in the path group, sending the same amount of IO to
+each.
+.TP
+.B "queue-length 0"
+Send the next bunch of IO down the path with the least amount of outstanding IO.
+.TP
+.B "service-time 0"
+Choose the path for the next bunch of IO based on the amount of outstanding IO
+to the path and its relative throughput.
+.RE
.TP
.B path_grouping_policy
The default path grouping policy to apply to unspecified
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