On 13 August 2012 08:42, Harsh J <[email protected]> wrote: > Hey Steve, > > Interesting, thanks for pointing that out! I didn't know that it > disables this by default :) > > It's always something to watch out for: someone implementing a disk FS, OS, VM environment discovering that they get great benchmark numbers if they make flushing async, and thinking "most people don't need it anyway". That's mostly true -and some programs over-flush-, but if you do want to be sure your data is saved to disk, these people are being dangerous rather than helpful
I don't think it's an issue if you are saving to network mounted storage -which can include the storage of the host OS. If you do some experiments, NFS chat to the host system is usually as fast as working with a virtual HDD in the same host OS -which has extra layers of indirection. Virtual HDDs can get fragmented even when the VM thinks it's just allocated big linear blocks -you need to defrag the virtual HDD then the physical disk image to correct that.
