Journal2 patches + timings + notes

Martin Langhoff martin.langhoff at gmail.com
Tue Dec 2 06:42:58 EST 2008


On Tue, Dec 2, 2008 at 4:27 AM, Michael Stone <michael at laptop.org> wrote:
> I also did a bit of timing on my XO, (see the 'timing' branch), wherein
> I learned, _anecdotally_ (i.e.  with sample-size n=1) that:
>
>   * startup time seems okay, but the initial query takes about 10s to
>     return results. I have about 300 MB of data indexed under
>     /home/olpc, plus a bit of other junk. (~/.pinot is ~ 35 MB).
>   * it takes around 4.2 seconds to fetch and display each new result
>   * the standard deviation in my sample was large, e.g. about 3.3 seconds.
>   * 19 results were fetched.

What is the size of teh data indexed there? Working with git internals
I quickly realised that there are some good trivial strategies
(ab)using the fs performance on linux that are simpler and faster than
using an "indexing library" as I've done in the past.

On a slow fs like jffs2, fancy indexers can be even worse than the
cheapskates fs techniques because mmapping may suck on jffs2 but
(ab)using directories doesn't...

cheers,



m
-- 
 martin.langhoff at gmail.com
 martin at laptop.org -- School Server Architect
 - ask interesting questions
 - don't get distracted with shiny stuff  - working code first
 - http://wiki.laptop.org/go/User:Martinlanghoff



More information about the Devel mailing list