One of the issues that has come up with multiplexing is that all of the bricks 
in a process end up sharing a single log file.  The reaction from both of the 
people who have mentioned this is that we should find a way to give each brick 
its own log even when they're in the same process, and make sure gf_log etc. 
are able to direct messages to the correct one.  I can think of ways to do 
this, but it doesn't seem optimal to me.  It will certainly use up a lot of 
file descriptors.  I think it will use more memory.  And then there's the issue 
of whether this would really be better for debugging.  Often it's necessary to 
look at multiple brick logs while trying to diagnose this problem, so it's 
actually kind of handy to have them all in one file.  Which would you rather do?

(a) Weave together entries in multiple logs, either via a script or in your 
head?

(b) Split or filter entries in a single log, according to which brick they're 
from?

To me, (b) seems like a much more tractable problem.  I'd say that what we need 
is not multiple logs, but *marking of entries* so that everything pertaining to 
one brick can easily be found.  One way to do this would be to modify volgen so 
that a brick ID (not name because that's a path and hence too long) is 
appended/prepended to the name of every translator in the brick.  Grep for that 
brick ID, and voila!  You now have all log messages for that brick and no 
other.  A variant of this would be to leave the names alone and modify gf_log 
so that it adds the brick ID automagically (based on a thread-local variable 
similar to THIS).  Same effect, other than making translator names longer, so 
I'd kind of prefer this approach.  Before I start writing the code, does 
anybody else have any opinions, preferences, or alternatives I haven't 
mentioned yet?

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