since it´s high latency, never will get sub milisecond right? so, master/master will be >milisecond for writes, reads are done locally here the solution is a master/slave
2011/4/5 Brian Moon <br...@moonspot.net>: > Products that do master/master across the WAN (or high latency LAN) and can > assure that a request to server A in datacenter 1 that sets a value is > available immediately (sub milisecond) to server B in datacenter 2? And that > does not involve making a connection back across the WAN to get the data? > Please do tell. > > Brian. > http://brian.moonspot.net > > On 4/5/11 4:44 PM, Roberto Spadim wrote: >> >> hummm i think it´s not innovative, there´s some open projects that >> solve this, you should check before developing the whell again >> >> 2011/4/5 Mohit Anchlia<mohitanch...@gmail.com>: >>> >>> Thanks everyone for replying. There is no easy solution for the >>> requirements being imposed upon us. Even though we have Oc3 still this >>> may not work sine memcached seems to be hash accross the servers >>> architecture and not master/master type architecture. >>> >>> I will have to come up with some other innovative idea to solve this >>> particular complex requirement. >>> >>> On Mon, Apr 4, 2011 at 11:23 PM, Dustin<dsalli...@gmail.com> wrote: >>>> >>>> On Apr 4, 9:28 pm, Roberto Spadim<robe...@spadim.com.br> wrote: >>>> >>>>> i'm using repcache without problem, if one server die the other have >>>>> the same information, when other server is up it's automatic sync with >>>>> the 'master' >>>>> it works well with php memcache session handler >>>>> but a good session handler could be a nosql database (membase) since >>>>> it's not a cache, it's a database... >>>> >>>> Membase doesn't currently have cross datacenter master/master >>>> replication that can compensate for inconsistencies introduced by >>>> network outages or latency when a user is jumping back and forth >>>> between two data centers. Anything that *can* is going to be much >>>> slower. >>>> >>>> I think Brian's got it there. Your best bet is to keep the users >>>> contained where networks are fast. RTT between SF and VA is something >>>> like 20ms. Replication doesn't help the situation. You might as well >>>> pin the data for the user in one data center and just fetch it across >>>> the country every time (which is effectively what AP systems will do). >>> >> >> >> > -- Roberto Spadim Spadim Technology / SPAEmpresarial
