You should be really careful when attempting to change the database server's -gn switch and you should be aiming to adjust it to a value that makes sense for your workload, not a documented 'maximum'. This is more of a practical limit for your workload situation - it will be different for each specific database use-case and hardware situation.

I would highly recommend first reading through this section of the documentation that talks about the effects of changing this value: http://dcx.sybase.com/index.html#1101/en/dbadmin_en11/running-s-3713576.html

While increasing the number of workers may improve your overall operation if there are a large number of unscheduled requests, increasing the number of workers unnecessarily will take away memory and resources from other workers and may cause higher amounts of contention, actually lowering throughput.

Since it's understood that this testing process is very experimental in nature and isn't practical to be run in each and every installation site, we now have automatic worker tuning in SQL Anywhere 12 and above.