tshipley@deru.com wrote: > In generic terms the database 101 class would say analyze your query to see if you can finagle the efficiency. A lot of reports link queries at the report/sub-report level, so look at the algorithm there. > > It is EASY to have a critical report that brings a system to its knees. Therefore, with any scale and $, DBAs replicate data from the transaction server to a report server. The report server doubles as a backup. > Sent from my BlackBerry Smartphone provided by Alltel > > -----Original Message----- > From: Joshua Zeidner > > Date: Wed, 8 Jul 2009 12:23:15 > To: Main PLUG discussion list > Subject: Re: PHP Script timing out and MySql using almost all the CPU and RAM > questions > > > sounds like you have either a MySQl bug or a problem query. Turn on > query logging and get the query that is causing the problem and post > it here. > > -jmz > > On Wed, Jul 8, 2009 at 12:21 PM, keith smith wrote: >> >> Hi Everyone, >> >> I do support for an online store. >> >> Last night we were trying to run a report that was taking forever. It is a lot of data so I expected it to timeout. The owner says he has successfully run the report before. I shelled in and found MySql was using 98.3% of the CPU and I think 4.7% of Memory. >> >> I restarted MySql and the load went down to nothing. >> >> While I was in there I noticed we have 513764k of RAM, and we were using almost all of it and we were using some swap as well. >> >> Here is what I just pulled off the system. >> >> top - 11:12:54 up 229 days, 20:08, 3 users, load average: 0.21, 0.16, 0.07 >> Tasks: 80 total, 2 running, 78 sleeping, 0 stopped, 0 zombie >> Cpu(s): 1.0%us, 0.3%sy, 0.0%ni, 95.7%id, 0.0%wa, 3.0%hi, 0.0%si, 0.0%st >> Mem: 513764k total, 506652k used, 7112k free, 4904k buffers >> Swap: 3723784k total, 32276k used, 3691508k free, 311520k cached >> >> >> This raises a number of questions: >> >> 1) What could cause the MySql server to start using so much CPU? After a restart we ran the report again and the CPU usage was much less. The report still timed out. >> >> 2) I'm wondering if more RAM would make the system more responsive? I've seen the benefits of RAM first hand but not in how it would speed up a web server. >> >> 3) The report we were running gave no indication of timing out. I'm wondering how the following PHP.ini directives come into play: >> >> - max_execution_time = 30 : In seconds. Why would the script appear to keep working? >> >> - max_input_time = 60 : Same question as above. >> >> I'm wondering if setting the memory - ini_set('memory_limit', '64M'); in that app, if that would help much and if I extend the time if that might help - ini_set('max_execution_time',240); along with ini_set("max_input_time", 240) ? >> >> Thanks in advance for your help! >> >> ------------------------ >> Keith Smith >> I've used that strategy numerous times. Depending on the query, adding an addition key/index can sometimes reduce reporting utilization substantially. -- -Eric 'shubes' --------------------------------------------------- PLUG-discuss mailing list - PLUG-discuss@lists.plug.phoenix.az.us To subscribe, unsubscribe, or to change your mail settings: http://lists.PLUG.phoenix.az.us/mailman/listinfo/plug-discuss