At first glance, this appeared to be a very egregious bug, but the effect is
actually minimal: since the size of the buffer is deterministic based on the
size of the data, you will have equal amounts of excess/junk data for equal
rows. Combined with the fact that 0.6 doesn't reuse these buffers, I don't
think we're actually doing any extra repair.
The problem is fixed in 0.7, but I've opened CASSANDRA-1729 to fix it in 0.6,
in case we start reusing row buffers.
Thanks for the report!
Stu
-----Original Message-----
From: "Schubert Zhang" <zson...@gmail.com>
Sent: Thursday, November 11, 2010 2:19am
To: dev@cassandra.apache.org, u...@cassandra.apache.org
Subject: MerkleTree.RowHash maybe a bug.
Hi JE,
0.6.6:
org.apache.cassandra.service.AntiEntropyService
I found the rowHash method uses "row.buffer.getData()" directly.
Since row.buffer.getData() is a byte[], and there may have some junk bytes
in the end by the buffer, I think we should use the exact length.
private MerkleTree.RowHash rowHash(CompactedRow row)
{
validated++;
// MerkleTree uses XOR internally, so we want lots of output
bits here
byte[] rowhash = FBUtilities.hash("SHA-256",
row.key.key.getBytes(), row.buffer.getData());
return new MerkleTree.RowHash(row.key.token, rowhash);
}
schubert.zh...@gmail.com
