I have two types of custom handhelds which are similar, but slightly different, each running the same WinForm application and a WinCE database:

Type 1: WinCE 4.2, 400 mhz, 93244 kb Type 2: WinCE 5.0, 520 mhz, 84208 kb

Type 1 will happily proceed through a large batch db operation (initiated) by the app, by Type 2 will consistently begin c-r-a-w-l-i-n-g (for several to many cycles) at around the 200 cycle mark. As several points it will begin running normally and then crawl again.

The app does several db op's (inserts, updates and selects, no deletes).

To simplify my situation, I've built a small test app which essentially does this:

command_s.CommandText = "select dvr from vr where vid = 2211250";
command_u.CommandText = "update pvr set LocationID=81 where Status='OK' and vri = 27861";

while(going)
{
    command_s.ExecuteScalar();
    command_u.ExecuteNonQuery();
}

and set it off running on the two units side by side. Sure enough, the slower (400 mhz) unit is outpacing the faster (520 mhz) unit (it's about 5000 cycles ahead right now) and I can see noticable pauses on the 520 mhz unit.

What is causing this?