[Bugs] [Bug 1272039] New: [Tier]: CPU shoots up to 200-300%age when a 1MB file is written from fuse client every 10 secs

[bugzilla at redhat.com]

https://bugzilla.redhat.com/show_bug.cgi?id=1272039

            Bug ID: 1272039
           Summary: [Tier]: CPU shoots up to 200-300%age when a 1MB file
                    is written from fuse client every 10 secs
           Product: GlusterFS
           Version: 3.7.5
         Component: tiering
          Severity: high
          Assignee: bugs at gluster.org
          Reporter: rhinduja at redhat.com
        QA Contact: bugs at gluster.org
                CC: bugs at gluster.org



Description of problem:
=======================

Volume has lots of data and when trying to write a 10MB file every 10secs from
fuse client. CPU usage for glusterfsd process jumps to 200-300%age as:

Tasks: 184 total,   2 running, 182 sleeping,   0 stopped,   0 zombie
%Cpu(s): 23.6 us, 47.8 sy,  0.0 ni, 25.4 id,  1.2 wa,  0.0 hi,  1.1 si,  1.0 st
KiB Mem :  3882184 total,  1610416 free,   870436 used,  1401332 buff/cache
KiB Swap:  2097148 total,  2097148 free,        0 used.  2681116 avail Mem 

  PID USER      PR  NI    VIRT    RES    SHR S  %CPU %MEM     TIME+ COMMAND     
14248 root      20   0 2111708  57584   4664 S 229.9  1.5  85:12.25 glusterfsd  
14230 root      20   0 2185444  60196   4696 S  63.5  1.6 130:21.93 glusterfsd  
14359 root      20   0 2498816  62376   4672 S   5.3  1.6  12:43.21 glusterfsd  
14445 root      20   0 1065268 126640   4728 S   0.3  3.3   3:51.64 glusterfs   
15170 root      20   0  146144   2052   1420 R   0.3  0.1   0:00.12 top         
    1 root      20   0  191352   6524   3892 S   0.0  0.2   0:02.98 systemd     



Version-Release number of selected component (if applicable):
=============================================================

glusterfs-3.7.5-0.19.git0f5c3e8.el7.centos.x86_64


How reproducible:
=================

Always


Steps Carried:
==============

1. Created 12 node cluster
2. Create tiered volume with Hot tier as (6 x 2) and Cold tier as (2 x (6 + 2)
= 16)
3. Fuse Mount the volume on 3 clients RHEL7.2,RHEl7.1 and RHEL6.7
4. Start creating data from each client:

Client 1:
=========
[root at dj ~]# crefi --multi -n 10 -b 10 -d 10 --max=1024k --min=5k --random -T 5
-t text -I 5 --fop=create /mnt/fuse/

Client 2:
=========
[root at mia ~]# cd /mnt/fuse/
[root at mia fuse]# for i in {1..10}; do cp -rf /etc etc.$i ; sleep 100 ; done

Client 3:
=========
[root at wingo fuse]# for i in {1..999}; do dd if=/dev/zero of=dd.$i bs=1M count=1
; sleep 10 ; done

5. After a while, the data creation of client 1 and client 2 should be
completed while the data creation from client 3 will still be inprogress

6. At this point the data creation will be of only 1 file from client 3 in
every 10 sec.

7. Monitor the cpu usage using top


Actual results:
===============

CPU usage jumps to >200%age for a while, reduces to 20-30%age and again jumps
to >200%age

-- 
You are receiving this mail because:
You are the QA Contact for the bug.
You are on the CC list for the bug.
You are the assignee for the bug.