# Strange mysql performance

**URL:** <https://www.ruby-forum.com/t/strange-mysql-performance/103219>\
**Category:** Rails\
**Created:** [May 3, 2007, 2:30am UTC](https://www.ruby-forum.com/t/strange-mysql-performance/103219 "2007-05-03T02:30:15Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![dawillis](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/d/ebca7d/32.png) [@dawillis](https://www.ruby-forum.com/u/dawillis)\
**Post date:** [May 3, 2007, 2:30am UTC](https://www.ruby-forum.com/t/strange-mysql-performance/103219/1 "2007-05-03T02:30:15Z")

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I have 3 boxes, each running Ubuntu Feisty. All of them are AMD64, one  
of them is in 32b mode, other two are 64b mode. All have the same  
filesystem type, and roughly the same hardware config. Each has the ruby  
mysql gem installed.

I have a script that fills a database with random data for testing. Its  
mainly a lot of inserts and takes about 30 to run on 2 of the boxes. On  
one of them (a 64b mode machine) it uses _very little CPU_ and takes  
FOREVER to run. I benchmarked the disk and its faster than the other HDs  
(this was done with repeated writes to a sqlite db), however this  
machine is the only one with a raid configuration.

Can anyone think of anything I should check out to fix this problem?

Thanks!!

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**Author:** ![dawillis](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/d/ebca7d/32.png) [@dawillis](https://www.ruby-forum.com/u/dawillis)\
**Post date:** [May 3, 2007, 4:59pm UTC](https://www.ruby-forum.com/t/strange-mysql-performance/103219/2 "2007-05-03T16:59:49Z")

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> machine is the only one with a raid configuration.
> 
> Can anyone think of anything I should check out to fix this problem?

Any chance the _C_ .so library for that mysql gem isn’t installed on  
that  
last box? I mean, the directory might be there and it might seem like  
it’s installed, but is the .so lib file there?

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<div class="post-metadata">

**Author:** ![dawillis](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/d/ebca7d/32.png) [@dawillis](https://www.ruby-forum.com/u/dawillis)\
**Post date:** [May 3, 2007, 5:31pm UTC](https://www.ruby-forum.com/t/strange-mysql-performance/103219/3 "2007-05-03T17:31:54Z")

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Check to see if you have write-back caching enabled in the RAID  
configuration.

DZ