Re: difficulties building PPL 0.11.2 without "--enable-shared"

[Anthony Foiani <anthony dot foiani at gmail dot com>]

Yann, all --

On Wed, May 18, 2011 at 10:34 AM, Anthony Foiani
<anthony.foiani@gmail.com> wrote:
> Although, I suspect that a better answer (for the purposes of ct-ng,
> at least) is to simply limit the interface languages to C and C++. ÂIt
> might be worth experimenting to see if limiting to just C saves a few
> more seconds; I suspect that the C++ interface is basically "free",
> since that's the native language of the library, but who knows...

A quick test from earlier today (5 reps for each case, varying which
language interfaces were selected, and the "-j" make argument):

  default    / j1:  719s total, 143s avg
  default    / j2:  636s total, 127s avg
  default    / j6:  627s total, 125s avg
  default    / j8:  619s total, 123s avg
  default    / j12: 624s total, 124s avg
  just_c     / j1:  409s total,  81s avg
  just_c     / j2:  340s total,  68s avg
  just_c     / j6:  332s total,  66s avg
  just_c     / j8:  327s total,  65s avg
  just_c     / j12: 335s total,  67s avg
  just_c_cpp / j1:  416s total,  83s avg
  just_c_cpp / j2:  343s total,  68s avg
  just_c_cpp / j6:  324s total,  64s avg
  just_c_cpp / j8:  323s total,  64s avg
  just_c_cpp / j12: 319s total,  63s avg

From this, I get:

1. It looks like it's almost twice as fast / half as long to build
only C and C++ instead of all the other interfaces (python, etc)

2. The parallel argument doesn't seem to make nearly as much of a
difference as I would have thought.  (This system might be slightly
IO-bound for this, though.)

System spec:

$ sudo hdparm -t -T /dev/sda6

/dev/sda6:
 Timing cached reads:   17922 MB in  2.00 seconds = 8978.38 MB/sec
 Timing buffered disk reads:  244 MB in  3.01 seconds =  81.03 MB/sec

$ grep 'model name' /proc/cpuinfo | uniq -c
      8 model name	: Intel(R) Core(TM) i7 CPU         930  @ 2.80GHz

Will finish putting together that patchset later this evening.

Best regards,
Tony

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