Tips for monitoring rails process memory leaks

Rails applications are more likely to encounter two types of performance problems: one is that rails executes slowly, the CPU consumes too much, and the other is a rails process memory leak. Solving both of these problems requires that you first pinpoint the problematic code before you know how to remedy the problem.

How to monitor the execution performance of rails processes

Positioning CPU high, slow execution of the rails code, is quite easy things, just need you to do a little statistical analysis of Production.log, extract the longest execution of the request, the problem is obvious. Because Production.log makes detailed statistics about the execution time of rails requests, for example:

Ruby Code

Completed　in　0.00693　(144　reqs/sec)　|　Rendering:　0.00489　(70%)　|　DB:　0.00000　(0%)　|　200　OK　[http://www.javaeye.com/]
Completed　in　0.17238　(5　reqs/sec)　|　Rendering:　0.10011　(58%)　|　DB:　0.06244　(36%)　|　200　OK　[http://www.javaeye.com/topic/49441?page=7]
Completed　in　0.20508　(4　reqs/sec)　|　Rendering:　0.19373　(94%)　|　DB:　0.00645　(3%)　|　200　OK　[http://www.javaeye.com/news/1586]

So we just need to write a line of shell commands, we're done! He screened out the top 500 most time-consuming requests and saved them to Timing.log.

Ruby Code

grep　"200　OK"　production.log　|　awk　'{print　"ALL:　"　$3　"　View:　"　$8　"　DB:　"　$12　"　URL:　"　$17　}'　\
|　sort　-r　|　head　-n　500　>　timing.log

Sort of good results for example:

Ruby Code

ALL:　5.51774　View:　5.38277　DB:　0.13338　URL:　[http://www.javaeye.com/wiki/topic/131966]
ALL:　5.51316　View:　5.31300　DB:　0.19400　URL:　[http://www.javaeye.com/wiki/topic/145383]
ALL:　5.51311　View:　5.39321　DB:　0.11234　URL:　[http://www.javaeye.com/wiki/topic/160370]
ALL:　5.51135　View:　5.37604　DB:　0.12652　URL:　[http://www.javaeye.com/wiki/topic/233365]
ALL:　5.49881　View:　5.35998　DB:　0.10637　URL:　[http://www.javaeye.com/wiki/topic/265217]

Which requests perform slowly, at a glance. Of course, in addition, we can monitor it in real time and display the request URL that rails is currently executing in the top Watch window.