Re: [patch] SMP alternatives

[Arjan van de Ven]

> Just a note to say glibc is getting better wrt to locking.
> Compare the results and trival test program here:
> http://lkml.org/lkml/2001/12/7/75
> That showed that for glibc 2.2.4, getc & putc
> were 669% slower than the unlocked versions.
> 
> 4 years later and with 2.3.5-1ubuntu1, getc & putc
> are only 230% slower than the unlocked versions:
> 
> $ dd bs=1MB count=100 if=/dev/zero | ./locked >/dev/null
> 100000000 bytes transferred in 3.709362 seconds (26958813 bytes/sec)
> $ dd bs=1MB count=100 if=/dev/zero | ./unlocked >/dev/null
> 100000000 bytes transferred in 1.602427 seconds (62405339 bytes/sec)

this could also mean that the unlocked version has gotten slower ;)



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