Ah-ha, I found it!
Anyone see the problem? If you want to cheat, you can look at the
ticket...
size_t num_read;
size_t total_read = 0;
while (size - total_read > 0 && (num_read = hdfsPread(fh->fs, fh-
>hdfsFH, offset + total_read, buf + total_read, size - total_read)) >
0) {
total_read += num_read;
}
if (num_read < 0) {
// invalidate the buffer
syslog(LOG_ERR, "Read error - pread failed for %s with return
code %d %s:%d", path, (int)num_read, __FILE__, __LINE__);
return -EIO;
}
return total_read;
Brian
On Dec 10, 2008, at 6:27 PM, Brian Bockelman wrote:
Hey,
In Hadoop-0.19.0, we've been getting crashing, deadlocking, and
other badness from libhdfs (I think: I'm using it through fuse-dfs).
https://issues.apache.org/jira/browse/HADOOP-4775
However, I've been at a complete loss to make any progress in
debugging. The problem happens consistently in our workflows, even
though it's been problematic to find a simple test case (I suspect
the issues are triggered by threading, while debug mode eliminates
any threading!). It doesn't appear there are any nice ways to debug
or follow along with actions in fuse_dfs or libhdfs: I don't even
know how to make DFSClient spill its guts to a log.
Help!
Brian
