@marcelo, we do want the changes requested in comment #5 in bug 1819689.
We can wait for the results of Long Li's investigation before proceeding

You received this bug notification because you are a member of Kernel
Packages, which is subscribed to linux-azure in Ubuntu.

   [linux-azure] Storage performance drop on RAID

Status in linux-azure package in Ubuntu:
Status in linux-azure source package in Xenial:
  Fix Committed

Bug description:
  In Azure, FIO 4k tests are showing performance drops on latest proposed 
4.15.0 linux-azure kernels - from 52K IOPS to ~38K IOPS (max value reached on 
both sequential and random read tests).
  The setup used is 12 disks in RAID0.
  The affected kernels are:
  Ubuntu 14.04 + 4.15.0-1043
  Ubuntu 16.04 + 4.15.0-1044

  Previous kernel versions had reached max IOPS, ~52K IOPS on both read
  tests (e.g. 16.04 + 4.15.0-1043 kernel). Right now, it seems like the
  issue is in the diff from 1043 kernel on trusty vs 1044 kernel on

  The 52K IOPS is expected at qdepth=256. The repro cmd (as ran by the 
automation) is this:
  fio --size=1023G --direct=1 --ioengine=libaio --filename=/dev/md0 
--overwrite=1 --readwrite=randread --bs=4K --runtime=300 --iodepth=32 
--numjob=8 --output-format=json 
--output=/root/FIOLog/jsonLog/fio-result-randread-4K-256td.json --name='repro'

To manage notifications about this bug go to:

Mailing list: https://launchpad.net/~kernel-packages
Post to     : kernel-packages@lists.launchpad.net
Unsubscribe : https://launchpad.net/~kernel-packages
More help   : https://help.launchpad.net/ListHelp

Reply via email to