private bool PreUpdate()
{
EnsureOpen();
bool hasEvents = false;
if (FlushControl.AnyStalledThreads() || FlushControl.NumQueuedFlushes() > 0)
{
// Help out flushing any queued DWPTs so we can un-stall:
if (InfoStream.IsEnabled("DW"))
{
InfoStream.Message("DW", "DocumentsWriter has queued dwpt; will hijack this thread to flush pending segment(s)");
}
do
{
// Try pick up pending threads here if possible
DocumentsWriterPerThread flushingDWPT;
while ((flushingDWPT = FlushControl.NextPendingFlush()) != null)
{
// Don't push the delete here since the update could fail!
hasEvents |= DoFlush(flushingDWPT);
}
if (InfoStream.IsEnabled("DW"))
{
if (FlushControl.AnyStalledThreads())
{
InfoStream.Message("DW", "WARNING DocumentsWriter has stalled threads; waiting");
}
}
FlushControl.WaitIfStalled(); // block if stalled
} while (FlushControl.NumQueuedFlushes() != 0); // still queued DWPTs try help flushing
if (InfoStream.IsEnabled("DW"))
{
InfoStream.Message("DW", "continue indexing after helping out flushing DocumentsWriter is healthy");
}
}
return(hasEvents);
}