There is one more relevant JIRA. We can keep the MVCC values as each Cell's "version" forever so we have clear view about the ordering of changes of Cells. In this way, we don't have to worry about clock skew & low time resolution OSs.
[BRAINSTORM] Combine MVCC and SeqId(https://issues.apache.org/jira/browse/HBASE-8763) On 5/23/14 5:56 PM, "Enis Söztutar" <[email protected]> wrote: >Also relevant: > >https://issues.apache.org/jira/browse/HBASE-8927 >https://issues.apache.org/jira/browse/HBASE-6833 > > >On Fri, May 23, 2014 at 5:54 PM, Enis Söztutar <[email protected]> wrote: > >> +1 to micros. We should do it at the table level rather than CF level? >> >> How can we get the micros resolution efficiently in java? >> >> Enis >> >> >> On Fri, May 23, 2014 at 5:27 PM, lars hofhansl <[email protected]> wrote: >> >>> We have discussed this in the past. It just came up again during an >>> internal discussion. >>> Currently we simply store a Java timestamp (millisec since epoch), i.e. >>> we have ms resolution. >>> >>> We do have 8 bytes for the TS, though. Not enough to store nanosecs >>>(that >>> would only cover 2^63/10^9/3600/24/365.24 = 292.279 years), but enough >>>for >>> microseconds (292279 years). >>> Should we just store he TS is microseconds? We could do that right now >>> (and just keep the ms resolution for now - i.e. the us part would >>>always be >>> 0 for now). >>> Existing data must be in ms of course, so we'd grandfather that in, but >>> new tables could store by default in us. >>> >>> We'd need to make this configurable both the column family level and >>> client level, so clients could still opt to see data in ms. >>> >>> Comments? Too much to bite off? >>> >>> -- Lars >>> >>> >> -- CONFIDENTIALITY NOTICE NOTICE: This message is intended for the use of the individual or entity to which it is addressed and may contain information that is confidential, privileged and exempt from disclosure under applicable law. If the reader of this message is not the intended recipient, you are hereby notified that any printing, copying, dissemination, distribution, disclosure or forwarding of this communication is strictly prohibited. If you have received this communication in error, please contact the sender immediately and delete it from your system. Thank You.
