Re: fat apache/mod_ssl/mod_php: big memory size on solaris
-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 thank for your answer I understand the RSS size. 72 M for VSize 4 M for RSS. swap used= +72M ex: if N apache launched, the size of swap used increase to N*Vsize. Second, i see something strange during my test, on 2 différent sparc (SunFire versus Netra) The same apache binary (72 M VSize) compiled on SunFire grow to (140 M VSize) on Netra. So on the last hardware, the swap available decrease dramatically. pmap -x $pid, show me on my netra, 2 blocks of 65M reserved for anon memory (shared memory perhaps). I suspect a bad tunning of my OS (sparc64-solaris2.9) or perhaps a bad tuning of the apache config. I will start an accurate debug, googling so much ;) If you have any idea or link regards. Ralf S. Engelschall wrote: Well, you said not RSS above, but only the RSS is what really counts here! The _virtual_ process size you can more or less completely ignore. Here the different Unix flavors always differ dramatically because of the way shared memory areas are counted, etc. So, as long as the RSS of your processes is about 10MB, everything is just fine. BTW, as a comparison: experience shows that a full-sized Apache usually grows up to 50MB in RSS after some processing time. For a small Apache I expect about 10MB RSS. The only thing you should keep in mind when comparing RSS values is that your system should be not already swapping as this fudges your comparison, of course. ;-) Ralf S. Engelschall [EMAIL PROTECTED] www.engelschall.com __ OpenPKG http://openpkg.org Developer Communication List openpkg-dev@openpkg.org -BEGIN PGP SIGNATURE- Version: GnuPG v1.4.5 (GNU/Linux) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org iD8DBQFF1N1oJR5cCX8pccMRAgS9AKCVn2VLViGZpx5/leszSfwR8zXL6QCg5QpY rUkGtCFDHVk1dlRCIZJGWIM= =WxCp -END PGP SIGNATURE- __ OpenPKG http://openpkg.org Developer Communication List openpkg-dev@openpkg.org
Re: fat apache/mod_ssl/mod_php: big memory size on solaris
On Thu, Feb 15, 2007, PLI wrote: I understand the RSS size. 72 M for VSize 4 M for RSS. swap used= +72M ex: if N apache launched, the size of swap used increase to N*Vsize. No, not directly. The VS mainly is RSS plus others parts which _could_ be swapped out. But usually they are not. They are _SHARED_ parts between the processes. If you spawn N Apache processes, each with 72MB VS and just 4MB RSS, it means that each Apache process requires 4MB of real RAM while all N Apache processes _together_ and just _once_ require about 72-4=68MB of real RAM. Sure, in practice this calculation is a little bit more complicated because the formula is more complex (as lots of different shared memory segments exists, also other types of memory exists, each Unix virtual memory subsystem does it partly different, etc), but as a general rule of thumb it is this way on a modern Unix system. Second, i see something strange during my test, on 2 différent sparc (SunFire versus Netra) The same apache binary (72 M VSize) compiled on SunFire grow to (140 M VSize) on Netra. So on the last hardware, the swap available decrease dramatically. No, unless the machine really starts swapping, it just means that the required shared memory between the Apache processes is larger. I don't know why, but _once_ 140MB is no problem (see above). pmap -x $pid, show me on my netra, 2 blocks of 65M reserved for anon memory (shared memory perhaps). I suspect a bad tunning of my OS (sparc64-solaris2.9) or perhaps a bad tuning of the apache config. I will start an accurate debug, googling so much ;) If you have any idea or link Well, you have a rather fat Apache (SSL plus PHP integrated), so it doesn't sound too strange that it consumes about 140MB of VS. As I said, I would not worry about this at this stage... Ralf S. Engelschall [EMAIL PROTECTED] www.engelschall.com __ OpenPKG http://openpkg.org Developer Communication List openpkg-dev@openpkg.org
