Thanks Jens! Your answer is pretty what I expected. Looks like I have to figure out the logic when pull and push data by myself instead of lazzzzzzzzzy just using continuous replication. : )
On Monday, November 2, 2015 at 4:23:14 PM UTC-5, Jens Alfke wrote: > > > On Nov 2, 2015, at 1:08 PM, [email protected] <javascript:> wrote: > > I'm using couchbase lite in a mobile app. Just wondering: > > • is there any limitation if I create continuous replication to sync data > between mobile device and server? > • How many concurrent continuous replication can be handled by one couchDB > or coubchbase server? > > > There’s not an easy answer to that; it depends on a lot of variables like > the server hardware, how busy the database is, etc. > > The hardest limit is the number of open TCP sockets the server can handle. > This is a general problem that connection-oriented protocols run into > (IMAP, XMPP, Comet, etc.) — it’s often called the “C10K Problem > <https://en.wikipedia.org/wiki/C10k_problem>”. The good news is that > Erlang and Go (the languages CouchDB and Sync Gateway are written in) are > both good at handling massive I/O concurrency. But you do need lots of > Ethernet adapters to support zillions of sockets on one machine! > > But generally, long before you hit limits like that, you’ll run into CPU, > RAM and I/O pressure on the server. Sync Gateway and Couchbase Server > support horizontal scaling — you can plug in any number of servers and rig > up a load-balancer to distribute requests among them. (CouchDB can do > something similar but you have to rig up all of the servers to replicate > their databases with each other, and I have doubts about the scalability of > that. There’s also a variant called BigCouch which is designed to scale > higher.) > > • If reach the limit, what will happen on mobile side and server side? > > > Most likely the clients will see longer and longer latency before > receiving updated documents, then eventually timeouts, then eventually > socket errors like connection-refused or connection-dropped. > > —Jens > > -- You received this message because you are subscribed to the Google Groups "Couchbase Mobile" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/mobile-couchbase/d400a163-9a66-4659-ab3b-6a0b7ae1dbe1%40googlegroups.com. For more options, visit https://groups.google.com/d/optout.
