[Gnu-arch-users] Re: more speed improvements

[Miles Bader]

With these changes I don't see much improvement on the emacs source tree
-- with inode-state, `tla what-changed' now takes about 24s with a cold
disk cache (vs. 30s yesterday).  It's about a 3x improvement over the
non-inode-state time, which is good, but still slightly frustrating.

I also saw what seemed to be strange results with the tla source tree:
it was taking _longer_ than emacs, even though it's only about 5% the
size!  However I then noticed that tla has a _massive_ number of
patch-logs, meaning the physical source tree is much bigger than the
nominal source tree.

Here's a summary of my test results; neither of these source trees had
any changed files, so the inode-state should be maximally useful.  I
figured out how to clear the disk cache reliably (my little cache-
clearing program had a _bug_!), so these should be more reliable than
yesterday's:

                                                       Timings[1]
                         Counts[2]        NO inode state     W/inode state
Tree           Size  files xtgs plogs    cold   hot  ucpu   cold   hot  ucpu
-------------  ----  ----- ---- -----    ----  ----  ----   ----  ----  ----
tla             4MB    451   10 1,224    0:33  0:09  8.4s   0:13  0:08  8.3s
emacs-lexbind  77MB  2,138  391    66    1:42  0:07  5.5s   0:24  0:04  3.7s

[1] cold = disk cache flushed, hot = source tree in disk cache, ucpu = user cpu
[2] files = number of source files according to `tla inventory -s'
    xtags = number of explicitly tagged files
    plogs = number of patch-logs (NOT included in `files')

I briefly glanced at the output of `strace' and it seemed like there
were way too many files being read, even now; I'm going to look at it
more later.

-miles

,timings
Description: tla timing results

-- 
In New York, most people don't have cars, so if you want to kill a person, you
have to take the subway to their house.  And sometimes on the way, the train
is delayed and you get impatient, so you have to kill someone on the subway.
  [George Carlin]