| 1 |
On Friday 24 January 2003 08:20 am, Toby Dickenson wrote: |
| 2 |
> Try running vmstat while emerging; do you actually see any disk activity? |
| 3 |
> On this machine with 500M ram, my last kde emerge barely touched the disks. |
| 4 |
|
| 5 |
Yeah, I'm completely with Toby on this one.... Because Linux aggressively |
| 6 |
caches disk access, I really wouldn't expect compiling on a RAM disk to do |
| 7 |
any better. If you have enough RAM for this to be feasible, the compilation |
| 8 |
is probably happening in RAM anyway (disk cache), so you'd gain nothing. |
| 9 |
|
| 10 |
The only thing I could possibly see confusing this is when you actually start |
| 11 |
having to swap out to disk. If page-outs that are swap-backed are very much |
| 12 |
more efficient than page-outs that are filesystem-backed, maybe then a RAM |
| 13 |
disk would give you a gain. |
| 14 |
|
| 15 |
I guess I wouldn't be surprised if page-outs to a swap partition are faster |
| 16 |
than page-outs to a filesystem, that's why Linux has swap partitions in the |
| 17 |
first place. But does anybody have concrete numbers proving that it actually |
| 18 |
matters in this particular case, that is, compilation? |
| 19 |
|
| 20 |
Evan |
| 21 |
|
| 22 |
-- |
| 23 |
gentoo-dev@g.o mailing list |
Archives