Re: [PERFORM] Increasing RAM for more than 4 Gb. using postgresql
Why dont you just grab the latest stable kernel from kernel.org, customize it, compile it and the see what happens? On Tue, 18 Jan 2005 09:35:12 +0700, [EMAIL PROTECTED] <[EMAIL PROTECTED]> wrote: > > I understand that the 2.6.* kernels are much better at large memory > > support (with respect to performance issues), so unless you have a > > 64-bit machine lying around - this is probably worth a try. > > > > You may need to build a new kernel with the various parameters : > > > > CONFIG_NOHIGHMEM > > CONFIG_HIGHMEM4G > > CONFIG_HIGHMEM64G > > > > set appropriately (or even upgrade to the latest 2.6.10). I would expect > > that some research and experimentation will be required to get the best > > out of it - (e.g. the 'bounce buffers' issue). > > In the standard rpm FC 2-3 with a newly install server , would it > automatically > detect and config it if I use the mechine with > 4 Gb [6Gb.] or should I > manually config it? > Amrit > Thailand > > ---(end of broadcast)--- > TIP 3: if posting/reading through Usenet, please send an appropriate > subscribe-nomail command to [EMAIL PROTECTED] so that your > message can get through to the mailing list cleanly > ---(end of broadcast)--- TIP 5: Have you checked our extensive FAQ? http://www.postgresql.org/docs/faqs/FAQ.html
Re: [PERFORM] Increasing RAM for more than 4 Gb. using postgresql
This must be a linux'ism because to my knowledge FreeBSD does not keep the os-cache mapped into the kernel address space unless it have active objects associated with the data. And FreeBSD also have a default split of 3GB userspace and 1GB. kernelspace when running with a default configuration. Linux people might want to try other os'es to compare the performance. Best regards, Nicolai Petri Ps. Sorry for my lame MS mailer - quoting is not something it knows how to do. :) - Original Message - From: "William Yu" <[EMAIL PROTECTED]> I inferred this from reading up on the compressed vm project. It can be higher or lower depending on what devices you have in your system -- however, I've read messages from kernel hackers saying Linux is very aggressive in reserving memory space for devices because it must be allocated at boottime. Josh Berkus wrote: William, The theshold for using PAE is actually far lower than 4GB. 4GB is the total memory address space -- split that in half for 2GB for userspace, 2GB for kernel. The OS cache resides in kernel space -- after you take alway the memory allocation for devices, you're left with a window of roughly 900MB. I'm curious, how do you get 1.1GB for memory allocation for devices? ---(end of broadcast)--- TIP 5: Have you checked our extensive FAQ? http://www.postgresql.org/docs/faqs/FAQ.html
Re: [PERFORM] Performance problem from migrating between versions!
Hi, I try it and it doesn't resolve the problem:( So, now what? To leave it that way for this query or There must be permanent solution because if other queries behave like that? Kaloyan Iliev Tom Lane wrote: Kaloyan Iliev Iliev <[EMAIL PROTECTED]> writes: Will ANALYZE resove this? Try it and find out. regards, tom lane ---(end of broadcast)--- TIP 8: explain analyze is your friend
[PERFORM] Disk configuration
I just wanted to bounce off the list the best way to configure disks for a postgresql server. My gut feeling is as follows: Keep the OS and postgresql install on seperate disks to the postgresql /data directory? Is a single hard disk drive acceptable for the OS and postgresql program, or will this create a bottle neck? Would a multi disk array be more appropriate? Cheers, Benjamin Wragg -- No virus found in this outgoing message. Checked by AVG Anti-Virus. Version: 7.0.300 / Virus Database: 265.7.0 - Release Date: 17/01/2005
Re: [PERFORM] Disk configuration
Benjamin, > I just wanted to bounce off the list the best way to configure disks for a > postgresql server. My gut feeling is as follows: > > Keep the OS and postgresql install on seperate disks to the postgresql > /data directory? > Is a single hard disk drive acceptable for the OS and postgresql program, > or will this create a bottle neck? Would a multi disk array be more > appropriate? All of this depends heavily on your database size, read/write balance, and transaction volume. For example, the PostgreSQL Press list runs fine on my single-drive IDE laptop (1 user, < 2mb database) but I wouldn't run the DBT2 (high-volume OLTP test) on it. More info? -- --Josh Josh Berkus Aglio Database Solutions San Francisco ---(end of broadcast)--- TIP 8: explain analyze is your friend
[PERFORM] Swapping on Solaris
Hello, I'm running PostgreSQL on a Solaris 8 system with 2GB of RAM and I'm having some difficulty getting PostgreSQL to use the available RAM. My RAM settings in postgresql.conf are shared_buffers = 8192 # min 16, at least max_connections*2, 8KB each sort_mem = 131072 # min 64, size in KB vacuum_mem = 131072 # min 1024, size in KB Ignoring the fact that the sort and vacuum numbers are really high, this is what Solaris shows me when running top: Memory: 2048M real, 1376M free, 491M swap in use, 2955M swap free For some reason I have 1.25GB of free RAM but PostgreSQL seems compelled to swap to the hard drive rather than use that RAM. I have the shared buffers set as high as the Solaris kernel will let me. I also know that Solaris will cache frequently used files in RAM, thereby lowering the amount of RAM available to an application, but my understanding is that Solaris will dump that cache if an application or the kernel itself requires it. The system has about 1,000 active email users using unix mailboxes which could what is keeping the database from exploiting as much RAM as available but my primary concern is to allow PostgreSQL to use as much RAM as it requires without swapping. What can I do to force the system to allow PostgreSQL to do this? Regards, Kevin Schroeder ---(end of broadcast)--- TIP 3: if posting/reading through Usenet, please send an appropriate subscribe-nomail command to [EMAIL PROTECTED] so that your message can get through to the mailing list cleanly
Re: [PERFORM] Swapping on Solaris
Kevin Schroeder wrote: Ignoring the fact that the sort and vacuum numbers are really high, this is what Solaris shows me when running top: Memory: 2048M real, 1376M free, 491M swap in use, 2955M swap free Maybe check the swap usage with 'swap -l' which reports reliably if any (device or file) swap is actually used. I think Solaris 'top' does some strange accounting to calculate the 'swap in use' value (like including used memory). It looks to me like you are using no (device or file) swap at all, and have 1.3G of real memory free, so could in fact give Postgres more of it :-) regards Mark ---(end of broadcast)--- TIP 4: Don't 'kill -9' the postmaster
