Warning: Serious space regression in HEAD

[Simon Marlow]

On 26/05/2011 18:58, Ian Lynagh wrote:
>
> Hi all,
>
> Need to dash now, so haven't checked properly, but I think there's a
> serious space regression in the HEAD. Be careful if doing a
> multi-threaded validate, or you may find yourself swapping heavily!

The nightly build time jumped by ~30 mins or so last night.

nofib compile times are up by 20%, comparing HEAD before the generics 
merge with last night's HEAD:

         -1 s.d.                -----           +8.7%
         +1 s.d.                -----          +31.9%
         Average                -----          +19.7%


My standard compile-performance test shows some increase when compiling 
Cabal, but only back to where 7.0.3 was.

7.0.3:
   13,377,509,376 bytes allocated in the heap
              250 MB total memory in use (0 MB lost due to fragmentation)
   Total time   24.46s  ( 27.57s elapsed)

HEAD before the generics merge:
   13,158,729,120 bytes allocated in the heap
              225 MB total memory in use (0 MB lost due to fragmentation)
   Total   time   23.94s  ( 27.07s elapsed)

HEAD now:
   13,223,847,896 bytes allocated in the heap
              250 MB total memory in use (0 MB lost due to fragmentation)
   Total   time   24.24s  ( 27.40s elapsed)

So it seems that large --make compilations aren't affected much, but 
short one-module compilations (as in nofib) are affected quite a lot.

Cheers,
	Simon