Re: fun (was Re: [Nmh-workers] some indexing results)

[Ralph Corderoy]

Hi Paul,

> ok so if there's no disk cache contention and the
> ~/Mail/inbox/mhindex.db file remains readable in disk cache, "scan"
> can finish in less than 1 second.
> 
> [snip]
> 0.144u 0.227s 0:00.37 97.2%     147+1426k 0+1io 0pf+0w
> #nsa:amd64# wc -l /tmp/vix2
>     3293 /tmp/vix2

Nice to see some effort in this area.  In future, could we have a
comparison with the stock scan run a few times too.  IIRC, it only reads
in as many blocks of an email's file as required to get what it needs so
that might fit into RAM too.

I consider this AMD Athlon XP 1600+ old but get

    $ \time scan +inbox first:3293 >$N
    0.36user 0.15system 0:00.60elapsed 87%CPU (0avgtext+0avgdata 0maxresident)k
    0inputs+24outputs (0major+3791minor)pagefaults 0swaps
    $ \time scan +inbox first:3293 >$N
    0.33user 0.17system 0:00.60elapsed 84%CPU (0avgtext+0avgdata 0maxresident)k
    0inputs+16outputs (0major+3792minor)pagefaults 0swaps
    $ \time scan +inbox first:3293 >$N
    0.35user 0.16system 0:00.60elapsed 86%CPU (0avgtext+0avgdata 0maxresident)k
    0inputs+16outputs (0major+3789minor)pagefaults 0swaps
    $ 
    $ strace -e read scan +inbox first:3293 2>&1 >$N |
    > awk '/^read/ {s += $NF} END {print s / 1024 / 1024}'
    12.5713
    $ 

Cheers,
Ralph.