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Re: Faster compilation speed


> > Do you have/can you get data for TLB misses?
> 
> I had done that on alpha, but didn't initially report the figures.  Would
> a comparison to 2.95 also be useful?

Certainly -- the numbers don't really mean anything unless we have 
something to compare them against.  Remember, gcc-2.95 bootstrap times 
were about half those that we have now (*after* taking into account new 
languages and libraries etc).

R.

> 
> gcc version 3.3 20020802 (experimental)
> 
> ---------------------------------------------------------------------------
> cc1 -O2 reload.i
> 
> issues/cycles = 0.51  issues/dcache_miss = 26.93  issues/dtb_miss = 1214.36

So if I understand these figures correctly, then 

dcache_miss/dtb_miss ~= 45

That is, one in 45 dcache fetches also requires a tlb walk.  How many dtb 
entries does an Alpha have?

> 
> ---------------------------------------------------------------------------
> cc1 reload.i
> 
> issues/cycles = 0.52  issues/dcache_miss = 31.29  issues/dtb_miss = 1854.16
> 

giving
dcache_miss/dtb_miss ~= 60





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