Date: Thu, 27 Mar 2003 12:45:41 +0300 (MSK) From: Igor Sysoev <is@rambler-co.ru> To: freebsd-hackers@FreeBSD.ORG Subject: Re: shared mem and panics when out of PV Entries Message-ID: <Pine.BSF.4.21.0303271215070.6715-100000@is> In-Reply-To: <3E8163C5.3024.3C0A1A9@localhost>
next in thread | previous in thread | raw e-mail | index | archive | help
On Wed, 26 Mar 2003, Andrew Kinney wrote: > Eventually, I may be forced to turn off KeepAlive and make use of If you disable keepalive I believe clients would not see much difference. Keepalive is a good feature for clients but it should be enabled if you have enough resources to support it. It can be enabled on light-weight server that uses kqueue and designed to handle the tens of thousands simultaneous connections. An overhead per connection would be several tens of kilobytes or less. A plain Apache without heavy modules spends hunderds of kilobytes of physical memory per connection. mod_perl spends megabytes or tens of megabytes of phycical memory per connection. In your untypical case Apache spends about 1.5M per connection of a kernel memory. > FreeBSD's accept filters My measurements on the loaded enough web sites show that the accept filters allow to save about 5-10% of Apaches. Of course they are the most effective without keepalives. But be sure use them only in between 4.1.1-RELEASE - 4.4-RELEASE, or 4.6-RELEASE and above. 4.5-RELEASE and -STABLE around have the syncache related bug that leads to DoS. > or put in a reverse proxy as you recommend. I can even recommend you one proxy - mod_accel - http://sysoev.ru/en/ > For now, though, we are serving the whole gammut > from this Apache. Static pages, images, mod_perl, PHP, > Apache::ASP, and most anything else a customer might want or > need to serve from a web server. I know it isn't the most efficient > way to use Apache, but nobody has any complaints about > performance at this point. You have too much overhead per connection and if the worload would grow you will have perfomance problems. Igor Sysoev http://sysoev.ru/en/
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?Pine.BSF.4.21.0303271215070.6715-100000>