Re: speed up onspaces utility

Posted in 2006

Topics: Server Administration, Platform-Specific Issues, Cloud, Docker & Containers

Martin Fuerderer — Mon, 25 Sep 2006 11:30:05 +0200 — source: Usenet: comp.databases.informix

Hi, are the devices cooked files in a file system? In that case I've seen that onspaces needs some time to "blow up" the file to the required size. This I think is due to several things, mostly I guess due to inefficient buffer size and system calls. Both of these are optimized rather for doing I/O by the server. When onspaces is doing the "blow up" of such files, it is not really necessary to use these system calls as there is no concurrency, etc. But I guess nevertheless onspaces uses these. This, together with inode creation by the system itself makes the operation slow. What you can do is to not only create the file before executing onspaces, but to also create it with the necessary size. E.g. system utility "dd" (like "dd if=dev/zero of=<file> bs=8388608 count=110" for your example) can be used for that, with a much more sufficient buffer size (in megabyte range), etc. After this inodes will already exist when executing onspaces and the onspaces operation is then faster. Of course you have to see whether the overall turnaround time then really is shorter. But there's a chance. Regards, Martin -- Martin Fuerderer IBM Informix Development Munich, Germany Information Management Informix URLs list: http://home.arcor.de/mfu1/informix/urls.html IBM Information On Demand Global Conference October 15-20, 2006, Anaheim, California see http://www.ibm.com/events/informationondemand informix-list-bounces@iiug.org wrote on 22.09.2006 17:45:20: > > We use raws stripped disk. IDS10 UC5, AIX 5.3 > > onspaces utility runing very slow, how can we speed it up? > > example, > onspaces -c -d dbphylog -p /usr/informix/dev-links/int1/DBPHYLOG_INT1 -o > 4 -s 896000 -m /usr/informix/dev-links/int1/MDBPHYLOG_INT1 4 > Thanks, > Frank > > > _______________________________________________ > Informix-list mailing list > Informix-list@iiug.org > http://www.iiug.org/mailman/listinfo/informix-list

↪ replying to Martin Fuerderer

hariog@yahoo.com — 25 Sep 2006 03:23:59 -0700 — source: Usenet: comp.databases.informix

May or may not be true in your case but I have seen slow performance issue with stripped array set has been setup with WRITE BACK policy. Check write policy.

↪ replying to Martin Fuerderer

hariog@yahoo.com — 25 Sep 2006 03:25:05 -0700 — source: Usenet: comp.databases.informix

May or may not be true in your case but I have seen slow performance issue with stripped array set has been setup with WRITE BACK policy. Check write policy.