-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 Andy,
On 5/8/12 6:41 PM, Andy Wang wrote: > Initial benchmarks seem to show that the behavior between tomcats > is not an issue. Do you mean that Tomcat performance appears to be the same regardless of version? That's both good and bad... I thought there were some performance improvements to the connectors from 5.5-> 6.0. Maybe that was 4.x->5.5. > Tomcat7 is using JDK 1.7 and this is interesting. The benchmarks > with tomcat7+jdk1.7 vary widely across the board (both through ajp > and direct http to tomcat) from 30s-40sMB/s. Java 1.6 seems alot > more consistent. Not sure why yet. That is interesting. On the other hand, the server /is/ on a virtual machine, and you never know what other processes are stealing focus. Many VMs are notorious for bad IO throughput (I'm looking at you, OpenVZ). > I've also moved off the crappy Windows XP VM I was provided to a > more recent Windows 2008 VM as well as a fresh Windows XP SP3 VM. > In past experience it seems windows XP and windows 2003 were the > worst of the bunch with the ajp downloads dropping as low as > 4-5MB/s over time. Have you tried bare hardware? > I'm going to run a barrage of tests and provide the numbers. Do > you think ab -n 5 and allowing ab to average the values of 5 hits > for the ~440MB iso is a sound average? Some tips for this kind of testing: 1. Don't run ab on localhost: all the numbers will be worthless 2. Run ab with a range of concurrencies, including c=1 3. Make /lots/ of requests. IMO, 5 requests is really a pinhole analysis. I would make as many requests as you can over 10 minutes and see what the throughput ends up being. > I'll compare Windows XP performance and Windows 2008 performance > and after that I'll do the same on a Linux VM to get a better > comparison. It will be good to see. If you want some really crappy scripts to get you going, feel free to start with mine from a while back (look in the "scripts" subdir): http://people.apache.org/~schultz/ApacheCon%20NA%202010/ Those scripts can run a ... lot of ab tests with lots of different concurrencies against a series of URLs -- that allows you to set up everything with, say, a different path or port number to get the various setups (bare httpd, httpd+mod_jk, httpd+mod_proxy, etc.) and then let it run all night. It will also produce some tables for you that can then easily be graphed. > I also did bump up the ajpPacket size to 64K with no noticeable > change to the benchmark numbers. So while 8k seems crappy it > doesn't seem to be an issue. Given that apache and tomcat are both > local I wouldn't expect that to be a big problem with 8k chunks > given the near non-existent latency of local connections. It's good to know that the packet size didn't affect performance, but I agree that localhost communication is always magically-fast no mater what. > I plan on doing both local ab requests as well as remote. The > problem with remote is that our network is busy, so it may account > for some variations but I don't think I can get our IT to segment > me anything for this purpose :(. Just get a crossover cable and use static IP addresses. > I'm not so concerned about a 25% hit. I'm really more concerned > with the drop to 4-5MB/s over time that seems to happen. Does this happen locally or only remotely? I wonder if you're hitting some kind of traffic-shaping or QOS rules on your own internal network. - -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/ iEYEARECAAYFAk+qxKYACgkQ9CaO5/Lv0PAs4QCgtAhZuB0Xc9MJJ0yo1YJPE3VQ P9UAoKRs+qE/DsdonYhCYI+WUkujCCoK =GVQX -----END PGP SIGNATURE----- --------------------------------------------------------------------- To unsubscribe, e-mail: users-unsubscr...@tomcat.apache.org For additional commands, e-mail: users-h...@tomcat.apache.org
