Re: NFS: low read/stat performance on small files

From: Jim Rees
Date: Fri Mar 23 2012 - 08:15:04 EST


Vivek Trivedi wrote:

204800 bytes (200.0KB) copied, 0.027074 seconds, 7.2MB/s
Read speed for 200KB file is 7.2 MB

104857600 bytes (100.0MB) copied, 9.351221 seconds, 10.7MB/s
Read speed for 100MB file is 10.7 MB

As you see read speed for 200KB file is only 7.2MB/sec while it is
10.7 MB/sec when we read 100MB file.
Why there is so much difference in read performance ?
Is there any way to achieve high read speed for small files ?

That seems excellent to me. 204800 bytes at 11213252 per sec would be 18.2
msec, so your per-file overhead is around 9 msec. The disk latency alone
would normally be more than that.
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