-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 André,
On 12/19/11 5:19 PM, André Warnier wrote: > On a 32-bit Linux system, this is what "top" has to say about the > memory usage of one tomcat 5.5 instance, running one single small > app, with -Xms128M -Xmx128M, and totally idle for the time being : > > PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND > > 2871 tomcat55 20 0 539m 137m 4560 S 0.0 9.1 129:40.19 jsvc > > If one multiplies this by 60, one gets : RES : +- 8 GB VIRT : +- 32 > GB The virtual size gets all muddied by recent JVMs that use shared memory between JVM processes to share the built-in types, etc. > There may be some overhead due to jsvc, but that would be the same > under Windows with tomcat55.exe. Not much. > Note also that on a 64-bit system like the OP, the numbers above > may be somewhat larger. Good thought: Eric, are you running 32-bit or 64-bit JVMs? You probably ought to run under 32-bit JVMs since you have no need for large heaps (if you intend to continue to run all several-dozen of these webapps in separate JVMs) and all that extra pointer room can really burn-through RAM quickly. If you must use a 64-bit JVM (why!?), you might want to look at using "compressed OOPS" which will shrink pointer sizes for Java objects. This may improve performance a bit too. > Which make me muse also that since the OP obviously doesn't need a > very large heap, he may benefit, maybe greatly, from running a > 32-bit JVM for his Tomcat instances, if that is allowed under his > version of Windows. He may gain even more by running his VM with a > 32-bit Windows in the first place. At least he's running his VM situation properly: with Linux as the host and Microsoft Windows as the guest. I've seen so many going he other way around and it baffles me. - -chris -----BEGIN PGP SIGNATURE----- Version: GnuPG/MacGPG2 v2.0.17 (Darwin) Comment: GPGTools - http://gpgtools.org Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org/ iEYEARECAAYFAk7vwIwACgkQ9CaO5/Lv0PD+2gCeIiWeAMkL4DeAgxKBIa0BUhKD GWMAnjgvwCQ876uytY1e+jdBfUtC3YZ3 =InPi -----END PGP SIGNATURE----- --------------------------------------------------------------------- To unsubscribe, e-mail: users-unsubscr...@tomcat.apache.org For additional commands, e-mail: users-h...@tomcat.apache.org
