Helpful to verify reports of your own downtime, or to double check a downed website you are trying to access.
One of a set of tools we are providing to everyone as a way of saying thank you for being a part of the community.
Course Of The Month
Become a Premium Member and unlock a new, free course in leading technologies each month.
Solved
IBM LPM performance issue
Posted on 2014-02-13
I recently had performance issues when I was LPM'ing a DB server from one frame to another, The server had 56GB and took almost an hour, But I have a similar machine with the same metrics and had 10% more load than the previous one which took only 40 min.
Also on the first one which I was LPM'd had application slowness and queries hanging, So does LPM have performance issues because IBM says its not the case...
Also on the first one which I was LPM'd had application slowness and queries hanging, So does LPM have performance issues because IBM says its not the case...
[X]
Welcome to Experts Exchange
Add your voice to the tech community where 5M+ people just like you are talking about what matters.
- Help others & share knowledge
- Earn cash & points
- Learn & ask questions
2-
2
4 Comments
Active today
If the whole system (not just the LPAR) in question runs near 100% (all CPUs) I can imagine that the small LPM overhead could have an effect on LPAR peformance, but if there's a bit CPU left no one should even notice that LPM is running (but see below).
If you don't have a dedicated connection LPM slowness could be due to network congestion, but from my experience the greatest impact on LPM speed is always by memory activity.
It's not the consumed amount of main memory which counts, it's the change rate.
A big amount of static memory can be transferred just easily, but continuously changing memory content is a challenge for LPM.
The more "dynamic" the memory is the longer LPM will have to try to transfer as much memory as possible, and the longer the whole process will take.
There is a short moment where LPAR processing has to be suspended in order to transfer the remaining memory content (which is too dynamic to be transferred on the fly) and to pass control to the target system.
The higher this amount of memory the longer the suspend time - this can potentially lead to application outages.
wmp
If you don't have a dedicated connection LPM slowness could be due to network congestion, but from my experience the greatest impact on LPM speed is always by memory activity.
It's not the consumed amount of main memory which counts, it's the change rate.
A big amount of static memory can be transferred just easily, but continuously changing memory content is a challenge for LPM.
The more "dynamic" the memory is the longer LPM will have to try to transfer as much memory as possible, and the longer the whole process will take.
There is a short moment where LPAR processing has to be suspended in order to transfer the remaining memory content (which is too dynamic to be transferred on the fly) and to pass control to the target system.
The higher this amount of memory the longer the suspend time - this can potentially lead to application outages.
wmp
thank you so much for the explanation, So u know how long is the theoretical suspend time according to IBM , Or Is this not published....
Featured Post
Question has a verified solution.
If you are experiencing a similar issue, please ask a related question
My previous tech tip, Installing the Solaris OS From the Flash Archive On a Tape (http://www.experts-exchange.com/articles/OS/Unix/Solaris/Installing-the-Solaris-OS-From-the-Flash-Archive-on-a-Tape.html), discussed installing the Solaris Operating S…
FreeBSD on EC2
FreeBSD (https://www.freebsd.org) is a robust Unix-like operating system that has been around for many years. FreeBSD is available on Amazon EC2 through Amazon Machine Images (AMIs) provided by FreeBSD developer and security office…
Learn how to find files with the shell using the find and locate commands.
Use locate to find a needle in a haystack.: With locate, check if the file still exists.: Use find to get the actual location of the file.:
This video shows how to set up a shell script to accept a positional parameter when called, pass that to a SQL script, accept the output from the statement back and then manipulate it in the Shell.
Suggested Courses
Earn Certification
HTML5 Specialist - Certification
Free withPremium
Course of the Month4 days, 1 hour left to enroll
630 members asked questions and received personalized solutions in the past 7 days.
Join the community of 500,000 technology professionals and ask your questions.