Bug 996746

Summary: Reading from glusterfs drive takes twice as much data transfer as what you read
Product: [Community] GlusterFS Reporter: Federico Leva <federicoleva>
Component: unclassifiedAssignee: bugs <bugs>
Status: CLOSED EOL QA Contact:
Severity: unspecified Docs Contact:
Priority: unspecified    
Version: pre-releaseCC: bugs, gluster-bugs
Target Milestone: ---   
Target Release: ---   
Hardware: Unspecified   
OS: Unspecified   
Whiteboard:
Fixed In Version: Doc Type: Bug Fix
Doc Text:
Story Points: ---
Clone Of: Environment:
Last Closed: 2015-10-22 15:40:20 UTC Type: Bug
Regression: --- Mount Type: ---
Documentation: --- CRM:
Verified Versions: Category: ---
oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
Embargoed:
Attachments:
Description Flags
Network graph of an instance after starting upload of some big files none

Description Federico Leva 2013-08-13 21:05:59 UTC 
Description of problem:
Reading from glusterfs is too slow and is easily capped; network consumption is twice as needed.

Version-Release number of selected component (if applicable):
$ glusterfs -V
glusterfs 3.3.1 built on Feb 14 2013 17:36:30
$ uname -a
Linux i-00000355 3.2.0-48-virtual #74-Ubuntu SMP Thu Jun 6 20:02:55 UTC 2013 x86_64 x86_64 x86_64 GNU/Linux

How reproducible:
Always

Steps to Reproduce:
1. Put some file on a glusterfs drive
2. Read the file and upload it somewhere else
3. Monitor the network stats

Actual results:
The download speed from glusterfs is exactly twice as the upload speed i.e. read speed, always and constantly. Typical situation:

NetHogs version 0.8.0

  PID USER     PROGRAM                                                                                                                       DEV        SENT      RECEIVED       
8151  root     /usr/sbin/glusterfs                                                                                                           eth0      36.996    7022.670 KB/sec
7417  nemobis  perl                                                                                                                          eth0    3364.814      21.309 KB/sec
?     root     10.4.0.218:47259-208.80.152.32:389                                                                                                       0.000       0.000 KB/sec
19530 root     /usr/sbin/glusterfs                                                                                                           eth0       0.000       0.000 KB/sec
11766 nemobis  sshd: nemobis@pts/0                                                                                                           eth0       0.000       0.000 KB/sec
?     root     unknown TCP                                                                                                                              0.000       0.000 KB/sec

  TOTAL                                                                                                                                              3401.810    7043.980 KB/sec 






Expected results:
Glusterfs sends me only the data I need, not wasting capacity over mysterious duplication of data transfer.

Additional info:
Tested from an instanceof wmflabs.org / Wikimedia Labs; I've noticed this for a long time now, also very easily seen on ganglia graphs.
Comment 1 Federico Leva 2013-08-13 21:07:05 UTC 
Too much whitespace...

NetHogs version 0.8.0

  PID USER     PROGRAM               DEV        SENT      RECEIVED       
8151  root     /usr/sbin/glusterfs   eth0      77.421   15704.657 KB/sec
7417  nemobis  perl                  eth0    7800.735      60.180 KB/sec
1097  nslcd    /usr/sbin/nslcd       eth0       0.000       0.000 KB/sec
19530 root     /usr/sbin/glusterfs   eth0       0.000       0.000 KB/sec
11766 nemobis  sshd: nemobis@pts/0   eth0       0.000       0.000 KB/sec
?     root     unknown TCP                      0.000       0.000 KB/sec

  TOTAL                                      7878.156   15764.838 KB/sec
Comment 2 Federico Leva 2013-09-09 06:26:39 UTC 
Created attachment 795504 [details]
Network graph of an instance after starting upload of some big files
Comment 3 Kaleb KEITHLEY 2015-10-22 15:40:20 UTC 
pre-release version is ambiguous and about to be removed as a choice.

If you believe this is still a bug, please change the status back to NEW and choose the appropriate, applicable version for it.