I did notice that even though I did 1,000 concurrent requests out of 100,000 total requests, the 100% margin of results showed a single request taking as long as the entire test. With `ab`, does it close and re-open the request after the 1,000? Hrm. I'm thinking my benchmarks may be unreliable due to this.
On Wed, Aug 19, 2009 at 8:36 PM, Kenneth Burgener <[email protected]>wrote: > On 8/19/2009 8:07 PM, Corey Edwards wrote: > > Kenneth Burgener wrote: > > > >> The overhead is due because when building a "new" connection there is a > >> lot of hurdles to pass: > >> > > And since he's specifically talking about HTTPS, the encryption overhead > > gets even worse. I'm not surprised at all to hear that keep-alive sped > > up the server by that much. > > > > Corey > > > > > True true. > > > And a follow up to my comments... > > Here is straight from the apache docs: > > "provide long-lived HTTP sessions which allow multiple requests to be > sent over the same TCP connection. In some cases this has been shown to > result in an almost 50% speedup in latency times for HTML documents with > many images" [1] > > Yes, that is 50% improvement, quoted from the apache documents. > > > And the reason that the KeepAlive is turned off by default is: > > "Each time a keep alive session is open and the client does not use it, > Apache will still keep the server process/thread busy and thus it won't > be able to accept another connection on that server - which will limit > the throughput." The solution to this problem is to either turn off > KeepAlive or set tight other restrictions such as MaxKeepAliveRequests > and KeepAliveTimeout (2-15 seconds is reasonable). > > It is highly recommended to set the > MaxKeepAliveRequests/KeepAliveTimeout to reasonable numbers so that, "A > limit is imposed to prevent a client from hogging your server > resources." [1] > > Kenneth > > > [1] http://httpd.apache.org/docs/1.3/mod/core.html#keepalive > > > /* > PLUG: http://plug.org, #utah on irc.freenode.net > Unsubscribe: http://plug.org/mailman/options/plug > Don't fear the penguin. > */ > -- Take care, William Attwood Idea Extraordinaire [email protected] Mike Ditka <http://www.brainyquote.com/quotes/authors/m/mike_ditka.html> - "If God had wanted man to play soccer, he wouldn't have given us arms." /* PLUG: http://plug.org, #utah on irc.freenode.net Unsubscribe: http://plug.org/mailman/options/plug Don't fear the penguin. */
