/// <summary>
/// Relinquish locks held during computation for a short while
/// and reacquire them.
/// </summary>
/// <remarks>
/// Relinquish locks held during computation for a short while
/// and reacquire them. This will give other threads a chance
/// to acquire the contended locks and run.
/// </remarks>
/// <returns>true if locks were released and reacquired.</returns>
public virtual bool Yield()
{
// Are we set up to do this?
if (limitPerRun <= 0 || dir == null || fsn == null)
{
return(false);
}
// Have we reached the limit?
long currentCount = counts.GetFileCount() + counts.GetSymlinkCount() + counts.GetDirectoryCount
() + counts.GetSnapshotableDirectoryCount();
if (currentCount <= nextCountLimit)
{
return(false);
}
// Update the next limit
nextCountLimit = currentCount + limitPerRun;
bool hadDirReadLock = dir.HasReadLock();
bool hadDirWriteLock = dir.HasWriteLock();
bool hadFsnReadLock = fsn.HasReadLock();
bool hadFsnWriteLock = fsn.HasWriteLock();
// sanity check.
if (!hadDirReadLock || !hadFsnReadLock || hadDirWriteLock || hadFsnWriteLock || dir
.GetReadHoldCount() != 1 || fsn.GetReadHoldCount() != 1)
{
// cannot relinquish
return(false);
}
// unlock
dir.ReadUnlock();
fsn.ReadUnlock();
try
{
Sharpen.Thread.Sleep(sleepMilliSec, sleepNanoSec);
}
catch (Exception)
{
}
finally
{
// reacquire
fsn.ReadLock();
dir.ReadLock();
}
yieldCount++;
return(true);
}