Re: Lockless page cache test results

KAMEZAWA Hiroyuki
2006-04-27T11:40:55Z

On Thu, 27 Apr 2006 13:16:25 +0200
Jens Axboe <axboe@suse.de> wrote:

> Added, 1 vs 2/3/4 clients isn't very interesting, so to keep it short
> here are numbers for 2 clients to /dev/null and localhost.
>
Thank you! looks splice has significant advantage :)

> Sending to /dev/null
>
> ml370:/data # ./splice-bench -n2 -l10 -a -s -z file
> Waiting for clients
> Client1 (splice): 19030 MiB/sec (10240MiB in 551 msecs)
> Client0 (splice): 18961 MiB/sec (10240MiB in 553 msecs)
This maybe shows cost of gathering page-cache.

> Client1 (mmap): 158875 MiB/sec (10240MiB in 66 msecs)
> Client0 (mmap): 158875 MiB/sec (10240MiB in 66 msecs)
This shows read/write system-call and user program cost. right ?

> Client1 (rw): 1691 MiB/sec (10240MiB in 6200 msecs)
> Client0 (rw): 1690 MiB/sec (10240MiB in 6201 msecs)
>
This shows 10240MiB copy_to_user() cost.
BTW, How big are cpu-cache-size and read/write buffer size in this test ?

> Sending/receiving over lo
>
read from a file and write to lo ?

> ml370:/data # ./splice-bench -n2 -l10 -a -s file
> Waiting for clients
> Client0 (splice): 3007 MiB/sec (10240MiB in 3486 msecs)
> Client1 (splice): 3003 MiB/sec (10240MiB in 3491 msecs)
> Client0 (mmap): 555 MiB/sec (8192MiB in 15094 msecs)
> Client1 (mmap): 580 MiB/sec (9216MiB in 16257 msecs)
> Client0 (rw): 538 MiB/sec (8192MiB in 15573 msecs)
> Client1 (rw): 541 MiB/sec (8192MiB in 15498 msecs)
>

Thank you.
-Kame