ubuntu - Is there any downside to setting ulimit really high? -

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i running problem many open files tomcat7 on ubuntu 12, increased hard , soft limit on number of open files 4096 , 1024, respectively, 16384. i'm not getting more errors open files, overall cpu% seems have risen. increasing number of max files have cost in cpu time? if not, why not set ulimit extremely high?

the entire reason ulimit exists protect overall performance of system preventing process using more resources "normal".

"normal" can different depending on doing, setting limits extremely high default defeat purpose of ulimit , allow process use ridiculous amounts of resources. on server without users less critical big multiuser environment, still useful safeguard against buggy or exploited processes.

your cpu went because computer doing more work instead of erroring out.

ps - want sure there isn't wrong in tomcat environment too... might ok have thousands of open files, don't know application, sign of gone buggy. if is, allowed bug's effect become potentially worse :( if can explain why tomcat needs thousands of files open, cool, if not... yikes.


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