Re: odd memory behaviour in 2.4.15

[Alan Cox]

> I have a separate linux machine with identical hardware
> running 2.4.15 which also ran well, until I upgraded its
> memory to 4GB. Then it ran 3 times slower than with 1 GB of RAM.

We end up copying data around a lot more with the 4 or 64Gb kernels. Some of
this unneccessarily. It may be down to your workload it might be a vm
quirk. Do the boxes all run the same workload.

Jens Axboe has patches for some setups that basically kill the slowdown
for all cases providing your I/O controller is sane