[GitHub] incubator-omid pull request #46: [OMID-90] Integrate omid low latency to pho...

[ohadshacham]

Github user ohadshacham commented on a diff in the pull request:

    https://github.com/apache/incubator-omid/pull/46#discussion_r223974301
  
    --- Diff: 
hbase-client/src/main/java/org/apache/omid/transaction/SnapshotFilterImpl.java 
---
    @@ -181,22 +179,44 @@ public CommitTimestamp locateCellCommitTimestamp(long 
cellStartTimestamp, long e
     
                 // 2) Then check the commit table
                 // If the data was written at a previous epoch, check whether 
the transaction was invalidated
    -            Optional<CommitTimestamp> commitTimeStamp = 
commitTableClient.getCommitTimestamp(cellStartTimestamp).get();
    -            if (commitTimeStamp.isPresent()) {
    -                return commitTimeStamp.get();
    +            boolean invalidatedByOther = false;
    +            Optional<CommitTimestamp> commitTimestampFromCT = 
commitTableClient.getCommitTimestamp(cellStartTimestamp).get();
    +            if (commitTimestampFromCT.isPresent()) {
    +                if (isLowLatency && !commitTimestampFromCT.get().isValid())
    +                    invalidatedByOther = true;
    +                else
    +                    return commitTimestampFromCT.get();
                 }
     
                 // 3) Read from shadow cell
    -            commitTimeStamp = 
readCommitTimestampFromShadowCell(cellStartTimestamp, locator);
    +            Optional<CommitTimestamp> commitTimeStamp = 
readCommitTimestampFromShadowCell(cellStartTimestamp, locator);
                 if (commitTimeStamp.isPresent()) {
                     return commitTimeStamp.get();
                 }
     
    +            // In case of LL, if found invalid ct cell, still must check 
sc in stage 3 then return
    +            if (invalidatedByOther) {
    +                assert(!commitTimestampFromCT.get().isValid());
    +                return commitTimestampFromCT.get();
    +            }
    +
                 // 4) Check the epoch and invalidate the entry
    --- End diff --
    
    or invalidate in a non latency mode


---