tomcat-users mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Peter Crowther <peter.crowt...@melandra.com>
Subject Re: Tomcat 100% CPU usage after moving from Java 5 to 6
Date Tue, 26 Jan 2010 17:51:31 GMT
2010/1/26 Leon Rosenberg <rosenberg.leon@googlemail.com>

> Another customer of mine was playing with gc settings for nearly a
> year, because his tomcats collection times went higher and higher, and
> after a short look at the heap dump with jmap and jhat, we found out
> that he had 100.000.000 uncollectable garbage objects in the heap (2/3
> of his heap actually). Instead of investigating his heap pollution he
> spent 11 month playing with gc options to setup a faster gc. In the
> end the problem was solved in two days.
>
> Definitely.  I've had the same in Smalltalk, the same in C# under the CLR.
Fewer live objects in the heap = faster GC.  Creating fewer short-lived
objects = less time spent in GC and in tenuring objects.  Almost always, the
root of a GC performance problem isn't the GC at all :-).

- Peter

Mime
  • Unnamed multipart/alternative (inline, None, 0 bytes)
View raw message