It is very difficult to compare the ehcache disk store and the JCS Indexed Disk Cache.
The JCS version is much more sophisticated. JCS puts items into a queue called purgatory. While they are in this queue, they are still accessible. This queue gets worked when items are in it. The number of threads used in the system as a whole for disk caches is configurable using the thread pool configuration options in JCS. I could have 1000 regions and only use 3 threads to work the disk queues. From what I can tell EH will use 1 thread per region. This is worse than the JCS default, which uses a queue that kills its threads when they are not used. . . . and much worse than using JCS with a thread pool. The size of JCS purgatory is configurable, so you can avoid catastrophe if something goes wrong with the queue worker. EH doesn't have any such safety. JCS limits the number of keys that can be kept for the disk cache. EH cannot do this. The ehcache disk version is very simple. It puts an unlimited number of items in a temporary store. You can easily fill this up and run out of memory. You can put items into JCS prugatory faster than they can be gc's but it is much more difficult. The EH store is then flushed to disk every 200ms. While EH is flushing the entire disk cache blocks! JCS disk cache is based on a continuous spooling model, not a stop the world model like EH. In most cases the EH model will work out, but not if you put a lot of big items on disk at once. The EH disk store also seems to just keep growing. After several tests, the size of the data file was 10 times that of JCS and EH was taking 10 times as long. You can saturate the EH version much more quickly, since it will hold as many items as you can put in in 200 ms. I tried with 100k and JCS could handle it, but EH died with an out of memory exception. 2006-02-16 13:47:04,166 [main] WARN net.sf.ehcache.config.ConfigurationFactory - No configuration found. Configuring ehcache from ehcache-failsafe.xml found in the classpath: jar:file:/C:/Documents%20and%20Settings/sg0894751/.maven/repository/ehcache/jars/ehcache-1.2beta4.jar!/ehcache-failsafe.xml 2006-02-16 13:47:04,446 [main] WARN org.apache.jcs.auxiliary.disk.indexed.IndexedDisk - Resetting data file JCS put time for 100000 = 5084; millis per = 0.05084 JCS get time for 100000 = 47368; millis per = 0.47368 Starting run for EHCache java.lang.OutOfMemoryError java.lang.OutOfMemoryError EH cache developed its disk store in response to a bug in the JCS version. This bug was fixed a few years ago . . . The nice thing about JCS is that it is completely pluggable. It would take about 30 minutes to plug a differnt disk cache implementation into JCS if you so pleased . . . . Aaron --- "Lane, Brad" <[EMAIL PROTECTED]> wrote: > I ran similar tests a couple months ago and came up > with the exact opposite > result. I also ran tests using disk cache and > EHCache was significantly > faster. > > -----Original Message----- > From: Alistair Forbes > [mailto:[EMAIL PROTECTED] > Sent: Thursday, February 16, 2006 2:11 AM > To: JCS Users List > Subject: Re: Initial performance test results: JCS > is almost twice as fast > as EHCache at gets and puts > > That is good news. Just for interest, which JVM > version are you using? > > On 2/16/06, Aaron Smuts <[EMAIL PROTECTED]> wrote: > > > > I just built both EHCache and JCS from head, > configured both similarly > > and ran multiple put / get rounds of 50,000. JCS, > using the default > > LRU Memory Cache, was nearly twice as fast as > EHCache in multiple > > trials for both puts and gets. I have the log > levels for both set at > > info. I would like to verify my results, since > they completely > > contradict the information on the EHCache site. > From what I can tell > > so far, JCS is significantly faster than EHCache. > > > > Since, neither will be a relevant bottleneck, it > may be beside the > > point. . . . I will run more tests to confirm. > > > > Here is the data: > > > > JCS put time for 50000 = 651; millis per = > > 0.01302 > > JCS get time for 50000 = 160; millis per = > > 0.0032 > > EHCache put time for 50000 = 481; millis per = > > 0.00962 > > EHCache get time for 50000 = 110; millis per = > > 0.0022 > > > > > > JCS put time for 50000 = 240; millis per = > > 0.0048 > > JCS get time for 50000 = 90; millis per = > 0.0018 > > EHCache put time for 50000 = 491; millis per = > > 0.00982 > > EHCache get time for 50000 = 120; millis per = > > 0.0024 > > > > > > JCS put time for 50000 = 241; millis per = > > 0.00482 > > JCS get time for 50000 = 80; millis per = > 0.0016 > > EHCache put time for 50000 = 551; millis per = > > 0.01102 > > EHCache get time for 50000 = 110; millis per = > > 0.0022 > > > > > > JCS put time for 50000 = 240; millis per = > > 0.0048 > > JCS get time for 50000 = 90; millis per = > 0.0018 > > EHCache put time for 50000 = 481; millis per = > > 0.00962 > > EHCache get time for 50000 = 130; millis per = > > 0.0026 > > > > > > JCS put time for 50000 = 230; millis per = > > 0.0046 > > JCS get time for 50000 = 181; millis per = > > 0.00362 > > EHCache put time for 50000 = 520; millis per = > > 0.0104 > > EHCache get time for 50000 = 101; millis per = > > 0.00202 > > > > > > JCS put time for 50000 = 220; millis per = > > 0.0044 > > JCS get time for 50000 = 90; millis per = > 0.0018 > > EHCache put time for 50000 = 641; millis per = > > 0.01282 > > EHCache get time for 50000 = 110; millis per = > > 0.0022 > > > > > > JCS put time for 50000 = 250; millis per = > > 0.0050 > > JCS get time for 50000 = 121; millis per = > > 0.00242 > > EHCache put time for 50000 = 590; millis per = > > 0.0118 > > EHCache get time for 50000 = 101; millis per = > > 0.00202 > > > > > > JCS put time for 50000 = 260; millis per = > > 0.0052 > > JCS get time for 50000 = 100; millis per = > > 0.0020 > > EHCache put time for 50000 = 581; millis per = > > 0.01162 > > EHCache get time for 50000 = 100; millis per = > > 0.0020 > > > > > > JCS put time for 50000 = 290; millis per = > > 0.0058 > > JCS get time for 50000 = 121; millis per = > > 0.00242 > > EHCache put time for 50000 = 570; millis per = > > 0.0114 > > EHCache get time for 50000 = 121; millis per = > > 0.00242 > > > > > > JCS put time for 50000 = 210; millis per = > > 0.0042 > > JCS get time for 50000 = 120; millis per = > > 0.0024 > > EHCache put time for 50000 = 561; millis per = > > 0.01122 > > EHCache get time for 50000 = 130; millis per = > > 0.0026 > > > > > > JCS put time for 50000 = 250; millis per = > > 0.0050 > > JCS get time for 50000 = 151; millis per = > > 0.00302 > > EHCache put time for 50000 = 560; millis per = > > 0.0112 > > EHCache get time for 50000 = 111; millis per = > > 0.00222 > > > > > > JCS put time for 50000 = 250; millis per = > > 0.0050 > > JCS get time for 50000 = 100; millis per = > > 0.0020 > > EHCache put time for 50000 = 711; millis per = > > 0.01422 > > EHCache get time for 50000 = 100; millis per = > > 0.0020 > > > > > > JCS put time for 50000 = 251; millis per = > > 0.00502 > > JCS get time for 50000 = 90; millis per = > 0.0018 > > EHCache put time for 50000 = 511; millis per = > > 0.01022 > > EHCache get time for 50000 = 90; millis per = > 0.0018 > > > > > > JCS put time for 50000 = 220; millis per = > > 0.0044 > > JCS get time for 50000 = 100; millis per = > > 0.0020 > > EHCache put time for 50000 = 491; millis per = > > 0.00982 > > EHCache get time for 50000 = 90; millis per = > 0.0018 > > > > > > JCS put time for 50000 = 230; millis per = > > 0.0046 > > JCS get time for 50000 = 80; millis per = > 0.0016 > > EHCache put time for 50000 = 201; millis per = > > 0.00402 > > EHCache get time for 50000 = 390; millis per = > > 0.0078 > > > > > > JCS put time for 50000 = 201; millis per = > > 0.00402 > > JCS get time for 50000 = 120; millis per = > > 0.0024 > > EHCache put time for 50000 = 180; millis per = > > 0.0036 > > EHCache get time for 50000 = 411; millis per = > > 0.00822 > > > > > > JCS put time for 50000 = 210; millis per = > === message truncated === --------------------------------------------------------------------- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
