Messages in this thread | | | Date | Mon, 17 Jan 2000 11:00:46 -0700 | From | "D. Lance Robinson" <> | Subject | Re: Performance question |
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Achim,
I'm not familiar with your driver, but there may be a scatter gather limit which only allows 64KB at a time.
<>< Lance.
Achim Leubner wrote:
> Hello, > > I'm the maintainer of the ICP Disk Array Controller driver (gdth) and > I have a performance question. > I read a big file on an ext2 filesystem under Linux 2.2.xx with "dd" > with a read block size of 1 MB. > In the gdth scsi driver and therefore on the controller I see > 1. read commands with a size of <= 64 KB only > 2. max. 2 simultaneous read commands only > If the commands are splitted into 64 KB I/O's, why I don't see 16 > simultaneous commands (64 KB * 16 = 1 MB) ? > Could the reason be the read ahead cache implemented in > mm/filemap.c ? > Is there any possibility to change any filesystem/kernel parameters > to get I/O's with greater size or to get more simultaneous I/O's ? > > Any hints are greatly appreciated. > > Regards > Achim > > > - > To unsubscribe from this list: send the line "unsubscribe linux-scsi" in > the body of a message to majordomo@vger.rutgers.edu
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