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Re: zero filling pages

On Wednesday, July 23, 2003, at 02:50 PM, Nat! wrote:

So still, I would like to chose to not have that security in trade off for speed.

As an example, if I run a big make session, I could do with out the zero filling time. I am not sayin its a bottleneck there, but it isn't helping either. If I compile 100 files, and I am running that through gcc, that means AFAIK 3 stages, let each of those use 32 MB memory or 8000 pages data, that'd be 2.4 Mpages to be zero filled, which would mean on my Cube more than a minute spent zero filling. Certainly won't break my neck, but also quite certainly (for me) superflous.

2.4 million pages is 9375 MB. I'm pretty sure a Cube can write to memory at somewhere between 400-600 MB/s (not remembering the exact figure), so the actual CPU time spent zero filling those 2.4 million pages should be roughly 20 seconds. If your measured rate of zero fills is 2.4 Mpages in >60s, it seems likely that the inherent VM overhead others have mentioned is hurting you much more than the zero fill.
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 >Re: zero filling pages (From: Nat! <email@hidden>)



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