The ofs_Stall is not coming from the OSS but from here:

https://github.com/xrootd/xrootd/blob/master/src/XrdOfs/XrdOfsHandle.cc#L203

It appears there's a modest contention on the file descriptor table -- one that does not particularly play well with what appears to be an ad-hoc implementation of a timed lock:

https://github.com/xrootd/xrootd/blob/master/src/XrdOfs/XrdOfsHandle.cc#L504

It's not obvious why one would utilize that instead of a wrapper around pthread_mutex_timedlock; it appears the hand-rolled version has similar guarantees as the standard function but worse performance.


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