Bug 1217467

Summary: *CRITICAL* request for update of pv
Product: [Fedora] Fedora Reporter: Ali Akcaagac <aliakc>
Component: pvAssignee: Jakub Hrozek <jhrozek>
Status: CLOSED ERRATA QA Contact: Fedora Extras Quality Assurance <extras-qa>
Severity: unspecified Docs Contact:
Priority: unspecified    
Version: 20CC: jhrozek
Target Milestone: ---   
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Hardware: Unspecified   
OS: Unspecified   
Whiteboard:
Fixed In Version: pv-1.6.0-1.fc22 Doc Type: Bug Fix
Doc Text:
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Clone Of: Environment:
Last Closed: 2015-05-17 06:38:28 UTC Type: Bug
Regression: --- Mount Type: ---
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
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Description Ali Akcaagac 2015-04-30 12:38:46 UTC 
I have an urgent request for a new pv package.

I changed a bunch of my script from using

dd if=/dev/zero of="dummy" bs="512MB" conv="fdatasync"

to

dd if="/dev/zero" bs="512MB" conv="fdatasync" | pv | dd of="/dev/sda" bs="512MB" conv="fdatasync" &> /dev/null

The first "dd" command line had a forked thread running all 60-120 seconds throwing out the progress made in file creation.

The second "dd" was meant to make it more "user friendly" getting rid of the forked thread.

The problem is as follows:

While the first command...
  498+0 records in
  498+0 records out
  254976000000 bytes (255 GB) copied, 2774.35 s, 91.9 MB/s
does nearly 100mb/s

The other command with piped pv only does ...
  91.3GiB 2:04:22 [12.3MiB/s]
12mb/s

Basicly this is 1/10 of the initial speed. When doing some cleanups I do run either command over night to clean up used space (to null the blocks on the harddisk). Normally this process takes aproximately ~1 hours (guessed) while the other took up to 4 hours (~7mb/s average).

The problem has been explained here:

http://blog.kylemanna.com/linux/2014/04/28/poor-pv-and-splice-performance/

The author has fixed the issue with the version 1.5.3 of pv (which is already at version 1.6.0).

If possible. Since this is a real "bottleneck" release a new package for Fedora 20 (and upwards).

Thanks
Comment 1 Fedora Update System 2015-05-04 07:48:36 UTC 
pv-1.6.0-1.fc20 has been submitted as an update for Fedora 20.
https://admin.fedoraproject.org/updates/pv-1.6.0-1.fc20
Comment 2 Fedora Update System 2015-05-04 07:48:43 UTC 
pv-1.6.0-1.fc21 has been submitted as an update for Fedora 21.
https://admin.fedoraproject.org/updates/pv-1.6.0-1.fc21
Comment 3 Fedora Update System 2015-05-04 07:48:49 UTC 
pv-1.6.0-1.fc22 has been submitted as an update for Fedora 22.
https://admin.fedoraproject.org/updates/pv-1.6.0-1.fc22
Comment 4 Jakub Hrozek 2015-05-04 07:50:50 UTC 
Please add karma to the updates!
Comment 5 Fedora Update System 2015-05-08 07:28:04 UTC 
Package pv-1.6.0-1.fc22:
* should fix your issue,
* was pushed to the Fedora 22 testing repository,
* should be available at your local mirror within two days.
Update it with:
# su -c 'yum update --enablerepo=updates-testing pv-1.6.0-1.fc22'
as soon as you are able to.
Please go to the following url:
https://admin.fedoraproject.org/updates/FEDORA-2015-7652/pv-1.6.0-1.fc22
then log in and leave karma (feedback).
Comment 6 Fedora Update System 2015-05-17 06:38:28 UTC 
pv-1.6.0-1.fc20 has been pushed to the Fedora 20 stable repository.  If problems still persist, please make note of it in this bug report.
Comment 7 Fedora Update System 2015-05-17 06:42:45 UTC 
pv-1.6.0-1.fc21 has been pushed to the Fedora 21 stable repository.  If problems still persist, please make note of it in this bug report.
Comment 8 Fedora Update System 2015-05-26 03:15:39 UTC 
pv-1.6.0-1.fc22 has been pushed to the Fedora 22 stable repository.  If problems still persist, please make note of it in this bug report.