Just to give an extreme example from another time, another galaxy. I had a z9-BC (I told you, long ago) with TSM Linux VM (Tivoli Storage Manager, the backup thingy) that moved data for replication purposes from a TS3500 to a TS3310 with six tape pairs. Reached almost 1 GB/s with very little CPU going on. You should have seen the wait on that. And yes, I used Barton's tooling to look at it together with Rob.
best regards, Pieter Harder ________________________________________ Van: Linux on 390 Port <[email protected]> namens Mark Post <[email protected]> Verzonden: maandag 24 april 2017 20:36 Aan: [email protected] Onderwerp: Re: Diagnose high wait >>> On 4/24/2017 at 04:34 AM, Christer Solskogen <[email protected]> wrote: > While we're at talking about high steal% , could somebody share some > insights about how to diagnose high wait%? On top of what Barton said, a high percent wait time can show up if a Linux system is using very little CPU time, but one or more tasks are doing a lot of I/O. If the system is using a lot of CPU, then it's more likely what Barton is talking about. Mark Post ---------------------------------------------------------------------- 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 more information on Linux on System z, visit http://wiki.linuxvm.org/ ---------------------------------------------------------------------- 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 more information on Linux on System z, visit http://wiki.linuxvm.org/
