buffering history text file writes

[Igor Timkin]

Ilya Etingof writes:
> Note, however, that the disk where my history lives is somewhat slow (you
> see the figures) so the saving resulted by this hack might not be really
> noticable if your history disks are so fast that your system spends just
> a few minutes a day on history writes.

fflush() != disk write. The data go to VM cache and become
visiable for other processes.

~2 years ago I made such hack without noticeable difference.

Can you run innd with and without this hack (and without any others
hardware/software chages) during 1+ hour and send average hiswrite time ?