On Thu, 2004-06-10 at 18:45, Tom Shilson wrote: > Adam said: > > But if you do *that* then > > there's no way you're doing a CMS RESERVE on the swap disk, which means, > > in turn, that you're using raw FBA access to the device, which is > > somewhat slower than using DIAG. > > Is this unique to SUSE or is this true for all distros? We run RedHat and > have a script that runs under init.d. It formats and does a swapon. Would > it be better to do something else?
You get better performance if you use a CMS RESERVEd VDISK-minidisk as swap space and access it with the DIAG DASD driver. You could certainly RESERVE it in CMS and then do a mkswap/swapon if you wanted, but since you need CMS to reserve it anyway, why not do SWAPGEN and just put it, as swap, in /etc/fstab? However, there's not an official DIAG driver for s390x. I think Lucius Leland wrote one, although it requires that you have less than 2GB virtual store defined to the guest, and if you have less than 2GB, then why are you running 64-bit anyway? Further, the difference between swap-on-VDISK-via-FBA-driver and swap-on-VDISK-via-DIAG driver is small compared to the difference between swap-on-VDISK vs. swap-on-real-DASD. Adam ---------------------------------------------------------------------- For LINUX-390 subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: INFO LINUX-390 or visit http://www.marist.edu/htbin/wlvindex?LINUX-390
