Date: Tue, 10 Jul 2001 17:00:50 -0500 From: Bill Fumerola <billf@mu.org> To: Joseph Lekostaj <lekostaj@mcs.anl.gov> Cc: hackers@freebsd.org Subject: Re: TCP Window Size Message-ID: <20010710170050.F47870@elvis.mu.org> In-Reply-To: <youu20kr24e.fsf@fluffhead.mcs.anl.gov>; from lekostaj@mcs.anl.gov on Tue, Jul 10, 2001 at 02:54:41PM -0500 References: <youu20kr24e.fsf@fluffhead.mcs.anl.gov>
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On Tue, Jul 10, 2001 at 02:54:41PM -0500, Joseph Lekostaj wrote:
>
> I've been trying to up my TCP window size from the default 16K and it's caused nothing but problems. From the info I've found so far, these are the sysctl i've changed:
>
> kern.ipc.maxsockbuffer=2097152
> net.inet.tcp.rfc1323=1
> net.inet.tcp.sendspace=524288
> net.inet.tcp.recvspace=524288
Good christ thats a lot of memory per socket. kern.ipc.maxsockets is
also fairly important to know here too. Nothing is going to prevent
the above values from getting out of hand, short of a huge amount of
memory dedicated to sockets.. see below...
> But if I do that, on boot I get all sorts of error messages about buffer space. i.e.:
>
> Jul 9 11:53:20 ccn64 portmap[180]: cannot create tcp socket: No buffer space available
> Jul 9 11:53:21 ccn64 inetd[199]: shell/tcp: socket: No buffer space available
> Jul 9 11:53:21 ccn64 inetd[199]: login/tcp: socket: No buffer space available
> Jul 9 11:58:55 ccn64 RPC::PlClient[243]: Cannot connect: No buffer space available
> Jul 9 11:58:55 ccn64 RPC::PlClient[246]: Cannot connect: No buffer space available
>
> Is there anything I'm missing?
The memory to support blowing 524k of memory per socket? As I recall
this memory is eaten as the sockets are created.
If you really think you need that much memory (you don't), you're going
to need to increase your socket memory to a lot more then 2097152....
I'd personally suggest just tuning net.inet.tcp.*space to 64k at most.
--
Bill Fumerola - security yahoo / Yahoo! inc.
- fumerola@yahoo-inc.com / billf@FreeBSD.org
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