On Wed, Dec 12, 2001 at 03:38:06PM -0800, H . J . Lu wrote:
> H.J.
> ----
> 3 files on USB:
>
> # ls -l
> total 5984
> -rwxr-xr-x 1 root root 1991481 Dec 8 21:44 dsc00002.jpg
> -rwxr-xr-x 1 root root 2432127 Dec 8 23:54 dsc00005.jpg
> -rwxr-xr-x 1 root root 1675563 Dec 8 23:59 dsc00009.jpg
>
> 1. 2.4.10-pre10
>
> # time /bin/cp * /tmp/
> real 0m0.623s
> user 0m0.000s
> sys 0m0.100s
>
> 2. 2.4.10-pre10aa1
>
> # time /bin/cp * /tmp/
> real 0m8.952s
> user 0m0.000s
> sys 0m0.190s
>
>
> 3. 2.4.10-pre11
>
> # time /bin/cp * /tmp/
> real 0m8.851s
> user 0m0.000s
> sys 0m0.170s
but the above have nothing to do with the blkdev-pagecache.
Blkdev-pagecache can matter only with blkdev accesses, blkdev-pagecache
cannot make any difference if the I/O passes through any fs (not via the
block_dev layer) like in the above case.
Can you try to take those cp under strace timestamp and see what's the
syscall that blocks?
Andrea
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This archive was generated by hypermail 2b29 : Sat Dec 15 2001 - 21:00:24 EST