> my web app opens a mysql and a memcached connection when php script > starts, and then close the database and memcached connection right > before php script finishes execution. > > Based on the logging info I have, what happened was that there was > something wrong with mysql. queries were taking very long, so both > mysql and memcached connection stayed open for seconds. After I > changed memcached connection to 5000, the mysql issued occurred again > the next morning and I found out there were about 3500 memcached > 'current connections', which is much higher than peak time around 500. > Imagine 3500 connections needed when I had it 1024 in config. So I > believe it crashed because of too many connections.
Like I said before, it's not supposed to crash on too many connections. Can you reproduce this in isolation? IE; start another instance on that box, then have a script open up 1000+ connections to it and see if it crashes? If you can you could get a gdb backtrace which would be useful.
