Hi Christophe, Please consider this series of patches. > > This series of patches help to make IO processing more common for > path-latency prioritizer, make the multipath.conf more user-friendly > and fixup the error of calculation on log scale standard deviation. > Thanks very much. Regards Guan On 2017/9/21 21:23, Guan Junxiong wrote: > Hi Christophe, > > Please consider this series of patches. > > This series of patches help to make IO processing more common for > path-latency prioritizer, make the multipath.conf more user-friendly > and fixup the error of calculation on log scale standard deviation. > > First, the SCSI-to-NVMe translations which was blamed broken has been removed > since linux kernel 4.13, so that SG_IO IOCTL used in the reading is not > supported. Instead, PATCH 1/4 drops sg_read method and uses direct IO > reading both for NVMe device and SCSI device. > > Second, the original prio_args for prioritizer is like this: 20|10 which > is somewhat unconvenient for user. PATCH 3/4 drops it and use a syntax that > similar to other prioritizers, for example : > "base_num=5 io_num=10". > > PATCH 2/4 can be an independent patch. > > Third, Martin has pointed that standard deviation in the path-latency prioritizer > is wrong. We have solved this and here come the PATCH 4/4. > > > Thanks > Guan Junxiong > > > Changes from V1: > * add PATCH 4/4 > * rebase on the 0.7.3 tag > > Junxiong Guan (3): > multipath-tools: use direct IO for path latency prioritizer > multipath-tools: move get_next_string to util > multipath-tools: use user-friendly prio_args for path-latency > > libmultipath/prioritizers/path_latency.c | 156 +++++++++++++++++++++++-------- > libmultipath/prioritizers/weightedpath.c | 10 +- > libmultipath/util.c | 9 ++ > libmultipath/util.h | 1 + > multipath/multipath.conf.5 | 2 +- > 5 files changed, 127 insertions(+), 51 deletions(-) > > Guan Junxiong (4): > multipath-tools: use direct IO for path latency prioritizer > multipath-tools: move get_next_string to util > multipath-tools: use user-friendly prio_args for path-latency > multipath-tools: calculate standard deviation on a logarithmic scale > for prioritizer path_latency > > libmultipath/prioritizers/path_latency.c | 321 ++++++++++++++++++++----------- > libmultipath/prioritizers/weightedpath.c | 10 +- > libmultipath/util.c | 9 + > libmultipath/util.h | 1 + > multipath/multipath.conf.5 | 2 +- > 5 files changed, 217 insertions(+), 126 deletions(-) > -- dm-devel mailing list dm-devel@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/dm-devel
