effect on write cache

[chrcoluk]

So I am considering this to control a service I use that pollutes the read cache with data that will get no hits or very low hit rate, sadly the service has no O_DIRECT feature. I am hoping this wil do what I want.

However my concern is if it also disables write cache akin to fsync I only want to disable read caching.

Is this possible, and if no can it be patched in?

[hhoffstaette]

You shuld be able to combine nocache with eatmydata, which will disable fsync and therefore prevent nocache from uncaching files that are under writeback. You will then successfully pollute your memory with writeback data. :)