Thanks for doing that erix.

'Lookup averaged 0.012486 seconds/record

Hm. Disappointed with that. I suspect a good deal of that time is down to writing the 1000 found records to the disk.

I suspect that if you commented out the print of the records and reran it, it'd be more in line with the numbers I get here:

for my $i ( 1 .. $N ) {
    my $rndRec = 1 + int rand( 160e6 );
#    printf "Record $rndRec: ";

    my $pos = binsearch( \$idx, $rndRec );
    if( $pos ) {
        seek DATA, $pos, 0;
#        printf "'%s'",
        scalar <DATA>;
    }
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The first number is the time taken to load the index. The second run is with a warm cache:

E:\>c:\test\1118102-searcher e:30GB.dat e:30GB.idx
16.8919820785522
Lookup averaged 0.009681803 seconds/record

E:\>c:\test\1118102-searcher e:30GB.dat e:30GB.idx
4.17907309532166
Lookup averaged 0.009416031 seconds/record
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Of course, if I run it on an SSD, it looks much nicer, especially as the cache warms up:

E:\>c:\test\1118102-searcher s:30GB.dat s:30GB.idx
33.1236040592194
Lookup averaged 0.000902344 seconds/record

E:\>c:\test\1118102-searcher s:30GB.dat s:30GB.idx
3.44389009475708
Lookup averaged 0.000789429 seconds/record

E:\>c:\test\1118102-searcher s:30GB.dat s:30GB.idx
4.35790991783142
Lookup averaged 0.000551061 seconds/record

E:\>c:\test\1118102-searcher s:30GB.dat s:30GB.idx
3.86181402206421
Lookup averaged 0.000482989 seconds/record

E:\>c:\test\1118102-searcher s:30GB.dat s:30GB.idx
4.66845011711121
Lookup averaged 0.000458750 seconds/record
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