On 09/13/2011 02:28 PM, Alex Bligh wrote: > > > --On 13 September 2011 14:05:41 +0200 Paolo > Bonzini<[email protected]> > wrote: > >>> I see you've got support for NBD_TIMEOUT in your patch set too. >>> That might be better broken out. >> >> It's just ioctl_cmd_to_ascii. > > doh. That's what I get for reading too fast. > >>> I get the feeling patch 3/4 is going not going to get applied. >>> I should really fix nbd-client so it doesn't need this. >> >> FWIW I've seen multiple reports of getting better performance _without_ >> NONROT, but I don't see anything particularly bad in that patch. Flags >> are just a hint, you can always ignore them. > > Indeed. > > The case where you want NONROT set is where the elevator of the server is > likely to outperform the client, and there is very little latency between > the two ends (i.e. client elevator merges gain nothing). Small client > VMs are an example. > > The case where you want NONROT unset is where the client elevator is useful > (e.g. big memory server) and where the server will heavily benefit from > adjacent requests being merged, e.g. where there is a caching strategy > which is heavily localised. > > Personally, I think NONROT unset is a better default, but then I haven't > done lots of timings. I would be interested to know how we came upon > the current default though. > >>> Out of interest, what kernel(s) have you compile-tested these >>> against? I'd quite like to get them into my standalone module >>> tree (which is far far easier to test against). >> >> 3.0.3 > > OK - I think my tree is based on 2.6.32, so I may have a little > work to do. >
Ping? Paolo ------------------------------------------------------------------------------ The demand for IT networking professionals continues to grow, and the demand for specialized networking skills is growing even more rapidly. Take a complimentary Learning@Cisco Self-Assessment and learn about Cisco certifications, training, and career opportunities. http://p.sf.net/sfu/cisco-dev2dev _______________________________________________ Nbd-general mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/nbd-general
