I''m seeing quite slow IDE write performance on Xenolinux-1.2 Native linux writes at 30MB/s to an ext2 fs, and Xenolinux DOM0 gets about 2MB/s (this is not a virtual disk extent). hdparm doesn''t work under xenolinux, but that is only part of the problem. Native linux writes at 6MB/s without any hdparm tuning. The SCSI hosts seem fine. native linux writes to scsi at 36MB/s and xen at 28MB/s. Is the IDE speed about what I should expect for xen-1.2 or did I screw up my configuration? ------------------------------------------------------- This SF.Net email is sponsored by: IBM Linux Tutorials Free Linux tutorial presented by Daniel Robbins, President and CEO of GenToo technologies. Learn everything from fundamentals to system administration.http://ads.osdn.com/?ad_id=1470&alloc_id=3638&op=click _______________________________________________ Xen-devel mailing list Xen-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/xen-devel
This seems quiet slow. Can you check the xen boot message for a warning if PIO is used? That might explain. I think there was something on the xen-devel list a while back. There might be two mentioning of PIO (or at least I think that used to be the case) one of them might be wrong. Rolf> -----Original Message----- > From: xen-devel-admin@lists.sourceforge.net [mailto:xen-devel- > admin@lists.sourceforge.net] On Behalf Of David Becker > Sent: 24 March 2004 14:34 > To: xen-devel@lists.sourceforge.net > Subject: [Xen-devel] IDE drives > > > I''m seeing quite slow IDE write performance on Xenolinux-1.2 > Native linux writes at 30MB/s to an ext2 fs, and Xenolinux DOM0 gets > about 2MB/s (this is not a virtual disk extent). hdparm doesn''t work > under xenolinux, but that is only part of the problem. Native linux > writes at 6MB/s without any hdparm tuning. > > The SCSI hosts seem fine. native linux writes to scsi at 36MB/s and > xen at 28MB/s. > > Is the IDE speed about what I should expect for xen-1.2 or did I screw > up my configuration? > > > > > > ------------------------------------------------------- > This SF.Net email is sponsored by: IBM Linux Tutorials > Free Linux tutorial presented by Daniel Robbins, President and CEO of > GenToo technologies. Learn everything from fundamentals to system > administration.http://ads.osdn.com/?ad_id=1470&alloc_id=3638&op=click > _______________________________________________ > Xen-devel mailing list > Xen-devel@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/xen-devel------------------------------------------------------- This SF.Net email is sponsored by: IBM Linux Tutorials Free Linux tutorial presented by Daniel Robbins, President and CEO of GenToo technologies. Learn everything from fundamentals to system administration.http://ads.osdn.com/?ad_id70&alloc_id638&op=click _______________________________________________ Xen-devel mailing list Xen-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/xen-devel
> > I''m seeing quite slow IDE write performance on Xenolinux-1.2 > Native linux writes at 30MB/s to an ext2 fs, and Xenolinux DOM0 gets > about 2MB/s (this is not a virtual disk extent). hdparm doesn''t work > under xenolinux, but that is only part of the problem. Native linux > writes at 6MB/s without any hdparm tuning.Take a look at the boot messages -- I suspect Xen hasn''t got a proper driver for your IDE chipset and is falling back to PIO. You could try porting the driver from Linux (which I expect will be easy), or wait until the new IO stuff is ready.> The SCSI hosts seem fine. native linux writes to scsi at 36MB/s and > xen at 28MB/s.I''m surprised you''re seeing such a drop. With our aacraid PERC3/Di cards we see (MB/s): xenolinux Write 28.3 Read 46.7 linux Write 29.2 Read 47.2 Are you sure you''re using the same part of the disk? It could be a driver version issue, but I find it surprising you''re seeing such a performance drop. Cheers, Ian ------------------------------------------------------- This SF.Net email is sponsored by: IBM Linux Tutorials Free Linux tutorial presented by Daniel Robbins, President and CEO of GenToo technologies. Learn everything from fundamentals to system administration.http://ads.osdn.com/?ad_id=1470&alloc_id=3638&op=click _______________________________________________ Xen-devel mailing list Xen-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/xen-devel
" Take a look at the boot messages -- I suspect Xen hasn''t got a
" proper driver for your IDE chipset and is falling back to PIO.
Yep, you are right. Xenolinux says PIO. I''ll add this chipset to my
todo list.
ide: Assuming 33MHz system bus speed for PIO modes; override with idebus=xx
ServerWorks CSB5: IDE controller on PCI bus 00 dev 79
ServerWorks CSB5: detected chipset, but driver not compiled in!
ServerWorks CSB5: chipset revision 147
ServerWorks CSB5: not 100% native mode: will probe irqs later
ide0: BM-DMA at 0x0700-0x0707, BIOS settings: hda:DMA, hdb:DMA
ide1: BM-DMA at 0x0708-0x070f, BIOS settings: hdc:DMA, hdd:DMA
hda: ST340016A, ATA DISK drive
hdc: LG CD-ROM CRN-8245B, ATAPI CD/DVD-ROM drive
ide0 at 0x1f0-0x1f7,0x3f6 on irq 14
ide1 at 0x170-0x177,0x376 on irq 15
hdc: ATAPI 24X CD-ROM drive, 128kB Cache
Uniform CD-ROM driver Revision: 3.12
hda: 78156288 sectors (40016 MB) w/2048KiB Cache, CHS=4865/255/63 PIO
(slow!)
" Are you sure you''re using the same part of the disk?
most likely not. I ran the scsi writes on two different hosts just as a
sanity check, and not as a rigorous check. Both were the same hardware
and may even have had other users on them. It was close enough to be labeled
''the same'' for my purposes.
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