phoronix benchmarks ext4 vs. btrfs

Adam Williamson awilliam at
Fri Mar 9 06:43:51 UTC 2012

On Thu, 2012-03-08 at 22:19 -0700, Chris Murphy wrote:
> I'm not sure how useful 'time' is as a benchmark for file copies.

Don't file transfers get cached and return to a console as 'complete'
long before the data is ever written, sometimes?

I'm pretty sure you sometimes hit the case where you copy 200MB to a USB
stick, it returns to the console pretty fast, but the light on the stick
is still flashing, and if you run 'sync', it sits there for quite a
while before returning to the console, indicating the transfer wasn't
really complete. So I'm not sure 'time'ing a 'cp' is an accurate test of
actual final-write-to-device.

Some of the above is wonky personal observation and some of it is
probably cargo culted, but...
Adam Williamson
Fedora QA Community Monkey
IRC: adamw | Twitter: AdamW_Fedora | adamwfedora

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