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@timhaines
Created May 1, 2010 11:41
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# IO speed tests on a new softlayer server using the cheap 500gb Sata drives.
#62500 blocks per gig
# want to double ram
# have 12gb, so want 24gb worth
# 62500 * 24 = 1500000
time sh -c "dd if=/dev/zero of=ddfile bs=16k count=1500000 && sync"
#paste output:
1500000+0 records in
1500000+0 records out
24576000000 bytes (25 GB) copied, 388.196 s, 63.3 MB/s
real 6m55.689s = 415.689 meaning 59.1 MB/S
user 0m0.256s
sys 0m52.359s
#run this to flush the previous file out of memory
dd if=/dev/zero of=ddfile2 bs=16K count=750000
#run this to read original file
time dd if=ddfile of=/dev/null bs=16k
#paste output
1500000+0 records in
1500000+0 records out
24576000000 bytes (25 GB) copied, 172.406 s, 143 MB/s
real 2m52.408s
user 0m0.216s
sys 0m18.469s
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