LWN: Comments on "User-data replication on NUMA systems"

User data Page replication

balbir-_singh — Tue, 02 Sep 2003 10:32:24 +0000

I think only executable text pages are replicated. As far as
I can remember data is never replicated (I worked on such systems
about two years ago).

The title can be misleading if what I am saying is correct.

Balbir

Numbers are off

corbet — Thu, 21 Aug 2003 15:52:09 +0000

I read the numbers right, I just wrote poorly. It was getting late in a long week... In any case, you're right; the new performance is as good as 143% of the old value, the improvement is 43%.

Numbers are off

pflugstad — Thu, 21 Aug 2003 15:19:31 +0000

I think you're looking at the numbers wrong. The posting has:

SDET Average Throughput (NUMA-Q):
2.6.0-test3 100.0%
2.6.0-test3+urepl 143.1%

SDET Average Throughput (16-way P4):
2.6.0-test3 100.0%
2.6.0-test3+urepl 108.8%

The baseline is 100%, so that's an *improvement* of 43.1% or 8.8%, not 143.2/108.8.

While these are good numbers, one wonders how the "production ready" patch would change them.