On Sat, Nov 2, 2013 at 3:24 PM, Christopher Schultz < ch...@christopherschultz.net> wrote:
> -----BEGIN PGP SIGNED MESSAGE----- > Hash: SHA256 > > Bob, > > On 11/1/13, 7:57 PM, Bob DeRemer wrote: > > > > > >> -----Original Message----- From: Christopher Schultz > >> [mailto:ch...@christopherschultz.net] Sent: Friday, November 01, > >> 2013 6:11 PM To: Tomcat Users List Subject: Re: attempting to > >> achieve 100K concurrent websocket connections on Tomcat 7.0.48 > >> NIO > >> > > Bob, > > > > Just a quick note: with NIO, you should not need 100k threads to > > serve 100k connections. Can a single process even request 100k > > threads from the OS under your current environment? > > > > > >> Hi Chris, > > > > As for a single client requesting 100K, no. There's a limit to the > > number of ephemeral ports outbound, but 40 - 50K is definitely > > doable per machine. > > I'm talking about threads, not connections. I don't doubt you could do > that many connections (though you might need a bit of > TCP/IP-stack-tuning to allow that many /concurrent/ connections). > > I'm concerned that your user is not permitted to start that many > threads and/or processes. You would be getting a different error, > though, in that case (likely "OutOfMemoryError: Cannot allocate a new > thread" or something like that). > > Ideally, you won't need anywhere near 100k threads to handle 100k > connections: that's the whole point (okay, well, half) of > Websocket-style communication of course. > > > We'll try setting maxThreads = -1 (like Mark mentioned), just to > > see how it works. With regard to machines, the client and server > > are both BIG EC2 instances with 16 vCPUs and 60 GB RAM. We were > > able to get 2 client machines, each running 1 java process > > simulating 40K websocket clients, connected to 1 Tomcat server > > instance - so 80K concurrent connections. It just seems that if we > > hit it too hard all at once, there are problems and we can't quite > > determine what's at the root of it. > > Interesting. That you can't apply the load all at once would indicate > a threading issue in Tomcat... otherwise things would just be slow at > the start of the test and then speed-up as the load smoothed-out. I > haven't yet read Mark's replies... he's likely got something fixed > already ;) > Could it be related to the EC2 infrastructure? When doing performance tests it's IMHO it's always preferable to have dedicated hardware. Controlled and deterministic environment helps the investigations. > - -chris > -----BEGIN PGP SIGNATURE----- > Version: GnuPG v1.4.15 (Darwin) > Comment: GPGTools - http://gpgtools.org > Comment: Using GnuPG with Thunderbird - http://www.enigmail.net/ > > iQIcBAEBCAAGBQJSdPz0AAoJEBzwKT+lPKRYttEP/RJCdC55J1ZpNNrPyN/zgEkj > p1AHYN/cMZoaBKjgS88tp++Lw8ewFrcnebja2Zfm4Exekg73/F0YACyPeC5i71JC > brIIjJD8nN9ycbQ7k9hjYCTn1soxfKy/LvAgpkame1qD9QHIEUqF2h2ptyjwkYWu > 3J1vLlA4ixHcUAVyvHGzKUvK/PvMwV57I2Y6QzIcENJK8QZIasE24bNB82JsK407 > +As2txOfOqWT+73asxsYPKlcu+sLOeGbvfLLmCpy8nQXd3hJcWWxt6XeSj6LGqmD > SntfVXEeeIY+nvTHlMsb+uY7aJmETk0q06T9T1hn/1fRUg3fhpNx/inzjr1+TVmt > cYMaSFPuXKHOVrG9eHihzA6AhY8jIQWARykpiQWUZvNcn/hhr7qV7IvpyCl5DL6F > 1LzwhnNRQQJ9XsOAqPeXTv9XLYEDTf3EDAnsJWrFVeuNwvTNtuyQoCiOJGDWyXFd > cX8ZnpKEEGC4U4493hG+0SSch8BwcuSwubH8LEspRAhbQneu456w1glJjsJIUgg0 > GmeTCwpEP2oJhjV1GUCKxomJCCN8ZsEPBozKrecZNP3xg7Ul/Fo7dhXxOrDnc6jr > Sypv3mERTaMVREqzbtNhJJPI5HVqlS3eaDjdm+UtWv1mfn7TKv0q7Q1mFUo/rHSh > aktcBF5/vNOiBhLTUU59 > =Vh4W > -----END PGP SIGNATURE----- > > --------------------------------------------------------------------- > To unsubscribe, e-mail: users-unsubscr...@tomcat.apache.org > For additional commands, e-mail: users-h...@tomcat.apache.org > >
