[ic] Interchange on FreeBSD

[Mike Heins]

I finally got a chance to bang on this for a bit. A few things
I discovered:


1. Use vlink, not tlink. Now it is tlink that has trouble on FreeBSD.
It may have troubles on other Unices.

2. The File::CounterFile module has major problems -- this is the 
source of the "bad counter magic" errors. There seem to be locking
issues on BSD that don't affect Linux or Solaris.

Try commenting out the count_ip(1) routine in lib/Vend/Session.pm.

It could be that I will add an additional counter method if I can find one
which works as well as I thought File::CounterFile did on all systems.

3. You are limited as much by socket connects as anything else.
I expect that I will be dealing with this soon, perhaps by 
selecting a random link socket file from a series of them....

ab is not a real good method for benchmarking MV. 8-) You either create
so many sessions that you end up causing more load than you would see,
or you lock yourself out as you contend for sessions. It works, though
it will fail on length a lot if your concurrency level is high.

Once I took the above steps, I ran requests simultaneously with
concurrency levels of 11 (on each of two systems, total 22 constant
simultaneous requests)  and failed to crash the machine in an hour. Though
it was breathing hard (only a 350MHz K6 with 128M) it survived. And
the major stuff is file and socket communication overhead; CPU States
averaged 63% system.

-- 
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phone +1.513.523.7621 fax 7501 <heins@akopia.com>

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