[DOC] innodb_adaptive_checkpoint description wrong

[In:Percona Server Documentation]
In the dscription of "innodb_adaptive_checkpoint" found here :http://www.percona.com/doc/percona-server/5.1/scalability/innodb_io.html, it says that the "estimate" flush method, "if the oldest modified age exceeds 1/2 of the maximum age capacity, InnoDB starts flushing blocks every second".
But In the source code of Percona-Server-5.1.70-rel14.8, I found that for "estimate" flush methold, it starts flushing when oldest modified age exceeds 1/4 of the maximum age capacity. Maybe we should modify the doc, change 1/2 to 1/4 .
See the source code as below:

in storage/innodb_plugin/srv/Srv0srv.c
line 3140

    } else if ((log_sys->lsn - oldest_lsn)
        > (log_sys->max_checkpoint_age)/4 ) {