And what about bad side effects from increasing the linger time? > -----Original Message----- > From: William A. Rowe, Jr. [mailto:wrowe@xxxxxxxxxxxxx] > Sent: Monday, November 20, 2006 12:50 PM > To: users@xxxxxxxxxxxxxxxx > Subject: Re: Tuning the MaxKeepAliveRequests and > KeepAliveTimeout http.conf parameters > > Arthur Kreitman wrote: > > > > I noticed a random but all to frequent (perhaps 1 or 2 or 3 for every > > few hundred http requests) error from ap_core_output_filter (about line > > 903 in core_filters.c). The error is an os 10054 "An existing > > connection was forcibly closed by the remote host". At the same time, > > the client side would believe the server performed a premature socket > > close. > > > > Regardless of the value of KeepAliveTimeout, if I set > > MaxKeepAliveRequests to 1 (ie no keep alive) the error occurs for almost > > 80% or 90% of the http requests > > > > If I don't set MaxKeepAliveRequests, which then uses the default value, > > by setting KeepAliveTimeout between 60 and 90 seconds, the error > disappears. > > DING DING DING - thank you for providing the essentials for a reproducible > test case!!! > > It sounds like we are not handling keep alive disconnection in the best > manner possible, leading to confusion by the ISAPI application. > > > My understanding of KeepAliveTimeout is that it plays with the socket > > linger option. What are the side effects of setting KeepAliveTimeout > > to a high value? What are the side effects of setting > > MaxKeepAliveRequests to a high value? > > 1. fewer workers available to handle high load > > 2. more exposure to denial of service (every daemon has an implicit denial > of service that it can handle only X parallel requests over N amount of > time - keeping N low helps mitigate this). > > Contra wise, the benefit is that the next request from the same client is > handled more quickly, if you assume that 'next page' requests will happen > within the keepalivetimeout period. > > > --------------------------------------------------------------------- > The official User-To-User support forum of the Apache HTTP Server Project. > See <URL:http://httpd.apache.org/userslist.html> for more info. > To unsubscribe, e-mail: users-unsubscribe@xxxxxxxxxxxxxxxx > " from the digest: users-digest-unsubscribe@xxxxxxxxxxxxxxxx > For additional commands, e-mail: users-help@xxxxxxxxxxxxxxxx --------------------------------------------------------------------- The official User-To-User support forum of the Apache HTTP Server Project. See <URL:http://httpd.apache.org/userslist.html> for more info. To unsubscribe, e-mail: users-unsubscribe@xxxxxxxxxxxxxxxx " from the digest: users-digest-unsubscribe@xxxxxxxxxxxxxxxx For additional commands, e-mail: users-help@xxxxxxxxxxxxxxxx
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