On Mar 8, 2011, at 9:48 AM, Les Mikesell <lesmikesell at gmail.com> wrote: > On 3/8/11 8:32 AM, Ross Walker wrote: >> >> Why wouldn't you want safe writes? Is that like saying, and if you care for your data? > > You don't fsync every write on a local disk. Why demand it over NFS where the > server is probably less likely to crash than the writing node? That's like > saying you don't care about speed - or you can afford a 10x faster array just > for the once-in-several-years you might see a crash. Well on my local disk I don't cache the data of tens or hundreds of clients and a server can have a memory fault and oops just as easily as any client. Also I believe it doesn't sync every single write (unless mounted on the client sync which is only for special cases and not what I am talking about) only when the client issues a sync or when the file is closed. The client is free to use async io if it wants, but the server SHOULD respect the clients wishes for synchronous io. If you set the server 'async' then all io is async whether the client wants it or not. -Ross