Messages in this thread |  | | | Date | Thu, 26 Apr 2012 21:53:44 -0400 | | From | Joe Ceklosky <> | | Subject | Possible 32-bit PAE kernel I/O slow down with 3.3.X |
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I have notice significant slow downs with disk I/O on a 32-bit PAE 3.3.X kernels.
The test machine has 16GB memory, Intel i5 CPU, Intel motherboard, and an Intel 160GB SSD. I copied 536M from one partition on an SSD to another. Yes, I should be using a 64bit kernel with 16GB!
Test 1: kernel 3.3.2 32-bit PAE with kernel parm mem=3G
time cp -ra testdir/ /tmp real 0m8.989s user 0m0.094s sys 0m1.080s
Test 2: kernel 3.3.2 32-bit PAE
time cp -ra testdir/ /tmp real 1m17.068s user 0m0.173s sys 0m2.149s
Also I tested kernel 3.2.16 32-bit PAE with no memory limits 16GB and it was in line with test 1.
I can repeat and provide any debugging information if needed.
Thanks, Joe Ceklosky
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