Not enough controller cache ?? Minidisk cache turned off ..?? - the best i/o is the one you don't do ..
Mark -----Original Message----- From: Richard Troth [mailto:[EMAIL PROTECTED] Sent: Thursday, August 17, 2006 10:03 AM To: [email protected] Subject: Re: I/O wait times -vs- Linux memory 3390 Vendor should not matter; these are on an EMC frame. What would bog Linux I/O to 3390s? -- R; ----- Original Message ----- From: Dave Jones [EMAIL PROTECTED] Sent: 08/17/2006 12:24 PM To: [email protected] Subject: Re: I/O wait times -vs- Linux memory Rick, what kind of Linux i/o are you doing? To real 3390s? To SHARKs looking like a 3390? To some sort of SCSI attached disk? DJ Richard Troth wrote: > We're looking at some high I/O wait times for a certain database. One > engineer has suggested that we add memory to Linux to speed things up. > I don't see it. Does adding RAM to Linux help its I/O throughput? > > We've put a lot of effort into sizing our Linux guests (all hosted by > z/VM 5.2) to that magical point between guest-level paging and excess > guest memory use, so some of us resist the thought of adding > real-to-Linux memory. I seems obvious that adding RAM would let any > access method do more buffering, but we want to avoid some of that > buffering because Linux gets carried away with it, correct? > > Thoughts? Thanks! > > -- R; > > > ---------------------------------------------------------------------- > 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 ---------------------------------------------------------------------- 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 ---------------------------------------------------------------------- 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 ---------------------------------------------------------------------- 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
