Hi all,
I have a 3G AM2 quad core CPU... x86_64 centos 5.3
When I am doing backing up to my external USB drive my system becomes sluggish. Clicking on a thunderbird compose takes some time to pop up the window. Typeing doesnt keep up etc...
Is there something I can change so this backup doesnt slow my system down so much? I dont see HOW it can be taking so much CPU. top at times shows 0 idle or 11% idle from a USB backup.
Thanks for any suggestions.
Jerry
On Fri, Jul 3, 2009 at 1:30 PM, Jerry Geisgeisj@pagestation.com wrote:
Hi all,
I have a 3G AM2 quad core CPU... x86_64 centos 5.3
When I am doing backing up to my external USB drive my system becomes sluggish. Clicking on a thunderbird compose takes some time to pop up the window. Typeing doesnt keep up etc...
Is there something I can change so this backup doesnt slow my system down so much? I dont see HOW it can be taking so much CPU. top at times shows 0 idle or 11% idle from a USB backup.
Thanks for any suggestions.
$ man renice
Didi
Jerry _______________________________________________ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Greetings,
On Fri, Jul 3, 2009 at 6:00 PM, Jerry Geisgeisj@pagestation.com wrote:
Hi all,
When I am doing backing up to my external USB drive my system becomes sluggish. Clicking on a thunderbird compose takes some time to pop up the window. Typeing doesnt keep up etc...
Is there something I can change so this backup doesnt slow my system down so much? I dont see HOW it can be taking so much CPU. top at times shows 0 idle or 11% idle from a USB backup.
also try out these
http://wiki.centos.org/HowTos/Disk_Optimization
Regards
Rajagopal
At Fri, 03 Jul 2009 08:30:43 -0400 CentOS mailing list centos@centos.org wrote:
Hi all,
I have a 3G AM2 quad core CPU... x86_64 centos 5.3
When I am doing backing up to my external USB drive my system becomes sluggish. Clicking on a thunderbird compose takes some time to pop up the window. Typeing doesnt keep up etc...
Is there something I can change so this backup doesnt slow my system down so much? I dont see HOW it can be taking so much CPU. top at times shows 0 idle or 11% idle from a USB backup.
Thanks for any suggestions.
Define 'backing up to my external USB drive':
Are you:
1) Using dump, tar, cpio, or cp? 2) Are you compressing the backup? With gzip or bzip? 3) Are you using zip?
If you are using bzip, bzip is a cpu hog.
How much memory do you have?
What kind of disks do you have? IDE? SATA? If SATA, is the controller in AHCI mode or IDE mode?
Jerry _______________________________________________ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
/
/>/ Hi all, />/ />/ I have a 3G AM2 quad core CPU... x86_64 centos 5.3 />/ />/ />/ When I am doing backing up to my external USB drive />/ my system becomes sluggish. Clicking on a thunderbird compose />/ takes some time to pop up the window. Typeing doesnt keep up etc... />/ />/ Is there something I can change so this backup doesnt slow my system />/ down so much? I dont see HOW it can be taking so much CPU. />/ top at times shows 0 idle or 11% idle from a USB backup. />/ />/ Thanks for any suggestions. / Define 'backing up to my external USB drive':
Are you:
- Using dump, tar, cpio, or cp?
- Are you compressing the backup? With gzip or bzip?
- Are you using zip?
If you are using bzip, bzip is a cpu hog.
How much memory do you have?
What kind of disks do you have? IDE? SATA? If SATA, is the controller in AHCI mode or IDE mode?
I have four gig RAM, I am just doing a "rsync -a /home /mnt/external_usb/backup.XX.YY.2009" My server has RAID-1 SATA 1 TB drives (two of course for raid) and I am doing a straight rsync to an external 1TB usb connected disk. Not doing any compression at this time.
The "renice" did help some mentioned earlier...
Jerry
On 2009-07-03 16:02, Jerry Geis wrote:
/>/ I have a 3G AM2 quad core CPU... x86_64 centos 5.3 />/ />/ />/ When I am doing backing up to my external USB drive />/ my system becomes sluggish. Clicking on a thunderbird compose />/ takes some time to pop up the window. Typeing doesnt keep up etc... />/ />/ Is there something I can change so this backup doesnt slow my system />/ down so much? I dont see HOW it can be taking so much CPU. />/ top at times shows 0 idle or 11% idle from a USB backup. />/ />/ Thanks for any suggestions. /
I have four gig RAM, I am just doing a "rsync -a /home /mnt/external_usb/backup.XX.YY.2009" My server has RAID-1 SATA 1 TB drives (two of course for raid) and I am doing a straight rsync to an external 1TB usb connected disk. Not doing any compression at this time.
The "renice" did help some mentioned earlier...
"ionice" is very usefull in this case as well.
If possible try to find a solution using eSATA instead of USB, which would work much smoother.
From: Jerry Geis geisj@pagestation.com
When I am doing backing up to my external USB drive my system becomes sluggish. Clicking on a thunderbird compose takes some time to pop up the window. Typeing doesnt keep up etc... Is there something I can change so this backup doesnt slow my system down so much? I dont see HOW it can be taking so much CPU. top at times shows 0 idle or 11% idle from a USB backup.
Reminds me of old CDROMs that would use an insane amount of CPU. Like the cheap RAID drivers that have a lot of the logic in the driver. Same for cheap winprinters. etc...
JD
on 7-3-2009 5:30 AM Jerry Geis spake the following:
Hi all,
I have a 3G AM2 quad core CPU... x86_64 centos 5.3
When I am doing backing up to my external USB drive my system becomes sluggish. Clicking on a thunderbird compose takes some time to pop up the window. Typing doesn't keep up etc...
Is there something I can change so this backup doesn't slow my system down so much? I don't see HOW it can be taking so much CPU. top at times shows 0 idle or 11% idle from a USB backup.
Thanks for any suggestions.
Jerry
USB I believe is not a DMA based port, so the processor has to do a lot of work, especially at higher speeds. Rsync can also be a resource hog, as it keeps most of the hash tables in memory it uses to compare files with.
Scott Silva wrote:
USB I believe is not a DMA based port, so the processor has to do a lot of work, especially at higher speeds. Rsync can also be a resource hog, as it keeps most of the hash tables in memory it uses to compare files with.
True enough, though I wouldn't say USB is the whole problem here, or maybe even the main one. Disk-to-disk backup amounts to a whole lot of I/O, and those pipes need continuous help from the CPU to stay full.
I have a similar system to the OP, except that it uses a hot-swap SATA disk instead of USB and rdiff-backup instead of rsync. Both improve the speed over the OP's solution, but even so, top shows the backup process regularly grabbing about 50% of one of the cores on a lightning fast Core i7 box to keep that pipe to the disk filled. When the backup is running, you easily feel the speed hit when doing other things at the same time.
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Didi -
Jerry Geis -
John Doe -
Paul Bijnens -
Rajagopal Swaminathan -
Robert Heller -
Scott Silva -
Warren Young