Could you explain why that is? What level of performance do you expect? Why would there be consistency problems?
> -----Original Message----- > From: Ted Dunning [mailto:[email protected]] > Sent: Mittwoch, 13. Juli 2011 19:55 > To: [email protected] > Subject: Re: Shared block storage via ZooKepper > > This would (roughly) work. It will not give very high performance and you > will have consistency problems. > > On Wed, Jul 13, 2011 at 10:37 AM, Yang <[email protected]> wrote: > > > assuming you use option 3) bookkeeper, the following is probably way > > too over-simplified, but that's the idea: > > > > all writers write to Bookkeeper ledger, and each of your actual > > datastore nodes keeps reading the ledger, each record would be the > > serialized form of a DB write op, and when the ledger reader reads out > > the record, it deserializes it, and applies it to the datastore it > > has, for example, just a mysql, or bdb, or something like the LSM tree > > used by Cassandra (memtable+sstable). > > > > reads to the store directly go to the data store nodes themselves. > > > > > > would this work? that does not sound a lot of work > > > > On Wed, Jul 13, 2011 at 3:02 AM, Simon Felix <[email protected]> wrote: > > > Hello everyone > > > > > > What is the best way to build a distributed, shared storage system > > > on top > > of > > > ZooKeeper? I'm talking about block storage in the terabyte-range (i.e. > > store > > > billions of 4k blocks). Consistency and Availability are important, > > > as is throughput (both read & write). I need at least 50 MB/s with 3 > > > nodes with two regular SATA drives each for my application. > > > > > > Some options I came up with: > > > 1. Use ZooKeeper directly as a data store (Not recommended according > > > to > > the > > > docs - and it really leads to abysmally bad performance, I tested > > > that) 2. Use Cassandra as data store 3. Use BookKeeper as > > > write-ahead log and implement my own underlying > > store > > > 4. Use ZooKeeper to create my own (probably buggy...) data store > > > > > > What would you recommend? Are there other options? > > > > > > Cheers, > > > Simon > > > > >
