>
>Hello
>I have a PC/Server with 2 Intel E6220 with 16GB ram, running Debian GNU / Linux 6.0 with kernel 2.6.32-5-xen-amd64.
>Adaptec controller has an ASR-2405 and am using the last module aacraid.ko (version 1.1-7 [28000]-ms)
>
>I have a significant drop in disk access performance when virtualizing Windows 2003 32Bit (Xen 4.0) and not if a topic module Xen aacraid.ko or incompatible with the module definition or bad domU
>
>I agracere any suggestions of where else to look.
>Below I detail my confuracion
>
>
>/-- In the controller, I have 4 drives (2 RAID 1)
>subsystem: Adaptec ASR-2405
>scsi0 : aacraid
>scsi 0:0:0:0: Direct-Access Adaptec R1sata V1.0 PQ: 0 ANSI: 2
>scsi 0:0:1:0: Direct-Access Adaptec R1sas V1.0 PQ: 0 ANSI: 2
>scsi 0:1:0:0: Direct-Access WDC WD5000AAKS-0 01.0 PQ: 1 ANSI: 5
>scsi 0:1:1:0: Direct-Access WDC WD5000AAKS-0 01.0 PQ: 1 ANSI: 5
>scsi 0:1:2:0: Direct-Access SEAGATE ST3300657SS 0006 PQ: 1 ANSI: 5
>scsi 0:1:3:0: Direct-Access SEAGATE ST3300657SS 0006 PQ: 1 ANSI: 5
>\-- In the controller, I have 4 drives (2 RAID 1)
>
>/--- The loaded modules are:
>lsmod | grep ata
>ata_generic 3239 0
>ata_piix 21124 0
>libata 133744 2 ata_generic,ata_piix
>scsi_mod 126501 5 sg,sr_mod,sd_mod,libata,aacraid
>\--- The loaded modules are:
>
>
>The performance of rad 1 (with two SAS drives) with "hdparm-tT / dev / sdb" is:
>/dev/sdb:
>Timing cached reads: 15192 MB in 1.99 seconds = 7636.45 MB/sec
>Timing buffered disk reads: 434 MB in 3.01 seconds = 144.02 MB/sec
>
>In this link you can see the performnce the SAS disk partition, with the parameter phy.
>
http://img96.imageshack.us/img96/7485/discosaswindowsdomu1.jpg
>
>In this link you can see that achieves performnce windows 2003 32bit host (native) of the same disk partition SAS
>
http://img838.imageshack.us/img838/7610/discosaswindowshost.jpg
>
>The xm dmesg is in the link
>
http://www.fileupyours.com/view/309484/xm_dmesg.txt
>
>/---------The domU.cfg is:
>kernel = '/usr/lib/xen-default/boot/hvmloader'
>device_model = '/usr/lib64/xen/bin/qemu-dm'
>builder = 'hvm'
>maxmen = '9216'
>memory = '9216'
>shadow_memory = 87
>acpi = 1
>apic = 1
>pae = 1
>vcpus =16
>videoram = 16
>
>disk = [
> 'phy:/dev/gv_db/vl2,ioemu:hda,w'
> ,'phy:/dev/gv_db/vl1,ioemu:hdb,w'
> ,'file:/mnt/domains/atreuco/disco3.img,ioemu:hdc,w'
> ,'phy:/dev/sdb2,ioemu:hdd,w'
>]
>boot='c'
>e1000=1
>vif = ['type=ioemu, bridge=eth0' ]
>usb =1
>usbdevice = 'host:0925:01003'
>\---------The domU.cfg is:
>
>Thank you for reaching this far down ...
>Sorry for English, this is google:)
>