> The good solution for this would be to put OOPS behind of apache. What is OOPS ?
Is it like SQL Relay ? Others have said that we should be using a connection pooler & that it's a PHP/Apache config problem that we're running into. We may also move to BSD from Redhat. > P.S Are you using mysql binary or version compiled with patched GLIBC > if not the threads limit should be the cause. We had to use the patched glibc. We have over 1,000 connections supported now. - Sam. On Monday, March 11, 2002, at 06:06 AM, Peter Zaitsev wrote: > Hello Michael, > > Monday, March 11, 2002, 3:38:28 PM, you wrote: > > > I had a close problem once - then having many active connections (and > so threads) mysql speed may degrade a lot because of scheduling and > convergency problem. This does not explain the mysql lock itself, but > may be the reason (i.e too many threads may make mysql to lock or > crush because of GLIBC limits) > The good solution for this would be to put OOPS behind of apache. > This gives two positive issues: > - your apache server will have much less children and so will require > much less memory and will basically work faster. In my case the > number of children have dropped from 150 to 16 and required memory > from about 1G to 200M (I'm running very complicated PHP scripts) > - you will need much less number of connections for mysql. In my > case the number have dropped from about 500 connections from web > server to 50, and load average on mysql server fell from 3.0-4.0 to > 0.5-1.0. > > > P.S Are you using mysql binary or version compiled with patched GLIBC > if not the threads limit should be the cause. > > > MW> Hi! > > Sam>> We have a very high volume site (3 million page views a day) > that's run > Sam>> on 16 Apache / PHP web servers & 2 MySQL servers. We are using > PHP with > Sam>> persistent connections. Each MySQL serves 8 web servers & is > supposed to > Sam>> act as a failover machine for the other group of 8 web servers. > Sam>> > Sam>> The failover won't work now as if one MySQL goes down the cost of > the 8 > Sam>> web servers switching over is so high the other MySQL locks up. > Sam>> > Sam>> Each Apache / PHP server takes up hundreds of connections even > when > Sam>> they're idle so we ran into the Linux connection limit of 1000 & > had to > Sam>> recompile to get past that. > Sam>> > Sam>> Our actual MySQL CPU useage is low but the goes when with the > connection > Sam>> overhead when starting up or failing over a bank of machines. > Sam>> > Sam>> We get a mysterious MySQL lockup once a week at the same day & > time. > > MW> Could you please describe the lookup, exactly what happens ? > > MW> What does 'mysqladmin var ext' show when this happens? > MW> What do you have in your log files ? > > Sam>> Questions : > Sam>> > Sam>> - Is our configuration of 2 sets of 8 Apache/PHP web servers & 1 > MySQL > Sam>> servers just not a good idea ? > > MW> This should not be a problem. > > Sam>> - Would we better off with FreeBSD ? > > MW> If you are running a CMP machine, then Linux preforms normally > better > MW> than FreeBSD. > > MW> To be able to give some recommendations we need to know more about > MW> this setup. > > Sam>> - Is there anyone doing any similar setups with lots of web > servers & a > Sam>> few MySQLs ? > > MW> We have several hundred of paying support customers with this setup. > > Sam>> - Is there any way to get Apache / PHP to use fewer connections ? > > MW> Stevens Rousseys exellent answer should help you with this > > Sam>> We pay for MySQL support but haven't had much help from them. > > MW> I checked our support email archive, but couldn't find anything from > MW> you or your company in it. > > MW> Could you please use our supportwizard interface to make a ticket of > MW> this problem so that we can help you with it? > MW> If you have already a ticket, please email me the ticket number so > MW> that we can check this up. > > MW> Regards, > MW> Monty > > > > > -- > Best regards, > Peter mailto:[EMAIL PROTECTED] >
