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I have a server with an ASUS board with a 256GB SSD

In Windows, using HDTune my drive shows 400MB/sec

on Linux, I'm getting about 2MB/sec using 

root@desktop:/# dd if=/dev/zero of=/foo bs=1024k count=100
100+0 records in
100+0 records out
104857600 bytes (105 MB) copied, 89.3776 s, 1.2 MB/s

any ideas what could be going wrong? the boss man is not happy and I am stumped :)

one clue may be that the 'Disks' utility on Ubuntu, using the Benchmark feature, gives the error "Error seeking to offset ... (g-io-error-quark, 13)

stuck
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  • Try a larger BS, like `1m`. Also, testing 64 MB of data is way too little to get a reasonable assessment of IO speed. You need to test at least 2x your RAM size to start eliminating cache influences. What driver is the SATA controller using? – Chris S Apr 12 '13 at 16:49
  • Can you please post the actual output? Also, my first guess is some sort of horribly misconfigured driver, or lack of TRIM usage on the Linux side. – Jeff Ferland Apr 12 '13 at 16:50
  • [post updated with bigger block size, dd output, and a clue with the Disks utility in Ubuntu] – stuck Apr 12 '13 at 17:08
  • I like the idea of driver misconfiguration - any tips there? I enabled TRIM (discard) and that didnt seem to help – stuck Apr 12 '13 at 17:34

1 Answers1

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thanks everyone for the tips - I have a solution!

the problem was I had x86 versions of Ubuntu installed - when I installed x64 the performance went to 560MB/sec measured from the 'Disks' application (which was failing on x86)

stuck
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