Thread: OS desicion
Hi List, I have a Dual-Xeon 3Ghz System with with GB RAM and an Adaptec 212ß SCSI RAID with 4 SCA Harddiscs. Our customer wants to have the Machine tuned for best Database performance. Which OS should we used? We are tending between Linux 2.6 or FreeBSD. The Database Size is 5GB and ascending. Most SQL-Queries are Selects, the Tablesizes are beetween 300k and up to 10 MB. I've read the Hardware Performance Guide and the result was to take FreeBSD in the Decision too :) And what is on this Context Switiching Bug i have read in the Archive? Hope you can help me Regards Tom
You are asking the wrong question. The best OS is the OS you (and/or the customer) knows and can administer competently. The real performance differences between unices are so small as to be ignorable in this context. The context switching bug is not OS-dependent, but varys in severity across machine architectures (I understand it to be mostly P4/Athlon related, but don't take my word for it). M Tom Fischer wrote: >Hi List, > >I have a Dual-Xeon 3Ghz System with with GB RAM and an Adaptec 212ß SCSI >RAID with 4 SCA Harddiscs. Our customer wants to have the Machine tuned >for best Database performance. Which OS should we used? We are tending >between Linux 2.6 or FreeBSD. The Database Size is 5GB and ascending. >Most SQL-Queries are Selects, the Tablesizes are beetween 300k and up to >10 MB. I've read the Hardware Performance Guide and the result was to >take FreeBSD in the Decision too :) > >And what is on this Context Switiching Bug i have read in the Archive? > >Hope you can help me > >Regards > >Tom > >---------------------------(end of broadcast)--------------------------- >TIP 3: if posting/reading through Usenet, please send an appropriate > subscribe-nomail command to majordomo@postgresql.org so that your > message can get through to the mailing list cleanly > >
Tom, > You are asking the wrong question. The best OS is the OS you (and/or > the customer) knows and can administer competently. I'll have to 2nd this. > The real > performance differences between unices are so small as to be ignorable > in this context. Well, at least the difference between Linux and BSD. There are substantial tradeoffs should you chose to use Solaris or UnixWare. > The context switching bug is not OS-dependent, but > varys in severity across machine architectures (I understand it to be > mostly P4/Athlon related, but don't take my word for it). The bug is at its apparent worst on multi-processor HT Xeons and weak northbridges running Linux 2.4. However, it has been demonstrated (with lesser impact) on Solaris/Sparc, PentiumIII, and Athalon. Primarily it seems to affect data warehousing applications. Your choice of OS is not affected by this bug. -- Josh Berkus Aglio Database Solutions San Francisco
Yes, quite right, I should have said 'popular x86-based unices'.<>The real performance differences between unices are so small as to be ignorable in this context.
Well, at least the difference between Linux and BSD. There are substantial
tradeoffs should you chose to use Solaris or UnixWare.
On Wed, Oct 20, 2004 at 09:38:51AM -0700, Josh Berkus wrote: > Tom, > > > You are asking the wrong question. The best OS is the OS you (and/or > > the customer) knows and can administer competently. > > I'll have to 2nd this. I'll 3rd but add one tidbit: FreeBSD will schedule disk I/O based on process priority, while linux won't. This can be very handy for things like vacuum. -- Jim C. Nasby, Database Consultant decibel@decibel.org Give your computer some brain candy! www.distributed.net Team #1828 Windows: "Where do you want to go today?" Linux: "Where do you want to go tomorrow?" FreeBSD: "Are you guys coming, or what?"