[jcifs] Peformance questions

[Philip Warner]

On 28/02/2013 3:45 PM, Michael B Allen wrote:
> JCIFS should absolutely not be querying DFS during writes and I would be surprised if it actually is. That is something that would
> require a proper capture to verify.

You are probably right about this, but based on 1.3.14 sources:

    SmbFileOutputStream.writeDirect(...) calls SmbFile.send(...)
    SmbFile.send(...) calls resolveDfs(...)
    resolveDfs(...) calls Dfs.resolve(...)

Dfs.resolve(...) looks like it does OS-level network stuff unless DFS is disabled, or unless it has succeeded in a call to
Dfs.resolve(...) recently.

My suspicion is that because DFS is enabled, and because DFS is not present, it is retrying for every block it sends. Hence the 400%
slowdown when DFS is enabled.

Or it could just the the OS-level calls are really slow.