[Standards] s2s and gracelessly broken streams

[Matthias Wimmer]

Hi Dave!

Dave Cridland schrieb:
> FWIW, I did some testing under Linux, and found that I could open 99997
> non-blocking sockets very quickly onto a dual Pent-III with 1G of RAM -
> hardly a powerhouse - using multiple desdtination ports. The limit was
> the compiled-in limit on the number of open file descriptors, and there
> was no other apparent impending exhaustion, as far as I could tell. (I
> wasn't pointinng these at an XMPP server, but an MSA, an IMAP server, a
> POP3 server, and an LDAP DSA, by the way, in roughly equal measure. All
> the services survived fine, but that doesn't tell me much of interest.)

If you are using libpth for example, you won't be able to have more than
1024 file descriptors. So considering the raw limits of the operating
systems is not enough, you have to consider the libraries running on top
as well.

But I won't really start counting connections on different systems.
Doesn't matter how many are possible, it is still a requirement for good
protocol design, to allow implementations to be conservative in resource
usage. When even some servers start to hold connections open to other
servers and these connected servers have now change to get rid of
connections if they have to get free resources again, you won't be able
anymore to implement servers on resource constrain systems.

(Hey where are the people in this thread, that even consider TLS
compression too resource expensive on their s2s links?)


Matthias

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