-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA256 Roy,
On 11/1/19 08:23, Roy Zhang wrote: > I am confused about "keep alive time" value in Embed Tomcat. I am > using Spring Boot 1.5, embed tomcat version is 8.5. > > According to > https://github.com/spring-projects/spring-boot/issues/16450#issuecomme nt-480236238, > > we can't configured thread's "keep alive time" via "maxIdleTime" > parameter, "keep alive time" value is hard coded as 60s via > https://github.com/apache/tomcat/blob/de1f55e672106031821948d5cac80f40 adc09513/java/org/apache/tomcat/util/net/AbstractEndpoint.java#L884, It > is only hard-coded if you use the internal, default Executor. You can instantiate your own Executor with whatever settings you wish. It's a bad name for that setting, but this is how long "excess" threads will live when they are not being used. > I found 60s "keep alive time" sometimes take effect, some times it > doesn't take effect. Could u please kindly help to review my > following two cases and kindly provide explanation? Really > appreciate ur help in advance! > > *Case 1 (60s "keep alive time" DOESN'T take effect):* API latency: > _100ms_ Test step: run API with 800 concurrent threads for 1 > minutes, then run API with 10 concurrent threads for about 1 hour. > As we can see from following graph, after BusyThreads reduced from > ~800 to 10, CurrentThreadsCount remains at 800 for following 1 hour > (60s "keep alive time" DOESN'T take effect). After test stopped, > CurrentThreadsCount reduced from 800 to 100(MinSpareThreads). > image.png Your images have been stripped from the mailing list. Find another way to describe your problem. When you say "X concurrent threads", how often are requests being made? Constantly? So you are sending requests as fast as possible with c=10? I haven't read the code in detail, but I'm guessing that the thread pool uses a queue and not a stack of threads, so each thread gets used, repeatedly, in order of availability. That means that if you keep making requests, you'll keep hitting *all* the threads in the queue and not just the same 10 over and over again. So they never time out. > *Case 2 (60s "keep alive time" DOES take effect):* API latency: > _10s_ Test step: run API with 800 concurrent threads for 1 minutes, > then run API with 10 concurrent threads for about 1 hour. As we can > see from following graph, after BusyThreads reduced from ~800 to > 10, CurrentThreadsCount reduced from 800 to 100(MinSpareThreads). > 60s "keep alive time" DOES take effect) Note that Tomcat's thread pool is just a wrapper around Java's ThreadPoolExecutor -- adding methods to handle Tomcat's lifecycle events, etc. So if the pool isn't behaving as you'd like it, you'll need to file a but against the Java API and not Tomcat. - -chris -----BEGIN PGP SIGNATURE----- Comment: Using GnuPG with Thunderbird - https://www.enigmail.net/ iQIzBAEBCAAdFiEEMmKgYcQvxMe7tcJcHPApP6U8pFgFAl28NzYACgkQHPApP6U8 pFjcRxAApIe9WPrO43rIn+8TZ/KBncZbw2ZQr/nEew1pS7xdRFl2LVn/gMpuYaIe 78rF/3M9S0aYcG93vaqzn1+BZXW5EI9EINo+UG3E17ZYeD162Cpl2Q7aqaB/Te0j QR/JHIv31TAUpH39VLEpzfk/d1uct7oVZDq4P3kUjjAFwAo2G0useiHjokXtdIEm 3wXL1e8ChpvdP8RfrPdeATdGtEvGh0zNDW2Qjce+7R5LoC55UpHqJfB+p8BB6nV/ W6Jdp8CN8pVp+wROMMyK3HFvubFqSPcrKGURCmwKMH/QgRfRSTNpIfXYpubfOOqm EF0XxvRc2s/x6ZqRrfnbkunqqmb0h35SXPaWl1RJWpe/cAAaHi0DGORorbDZfnff agzNvl7Wl0/6HL09CXr2PHU6ZQGytSYbItVAjEHqLKhbYW4pLKviLYB84ZRiEc5N 2ZA2ZE9VKWQRgu1kS25U4c5R7Zgy5oVAAIPLzNqEdcqu2dXSsZZeW4sJutwjioOL pia5qqRcotdDPxATqv0Eo75cqvvgE5WeWZ/tMb2sVia85UPRL/cJCgrc/+HmYPmb JRzhobGhQ7WA33yqRfvBdcJ5HIGe2aU4o06VoAv6tHXPldjD4jQ/YHyyicP+bj6E wswEM7oIAIU8+R7JFp1Lhv6ZMuLlKohDmOu2bubhAgweSrAQ8jY= =901h -----END PGP SIGNATURE----- --------------------------------------------------------------------- To unsubscribe, e-mail: users-unsubscr...@tomcat.apache.org For additional commands, e-mail: users-h...@tomcat.apache.org
