DOWN! Error: skipped indexing of internal audit event will keep dropping events until indexer congestion is remedied. Check disk space and other issues that may cause indexer to block

Good morning,

I am suddenly receiving this error and not able to index:

skipped indexing of internal audit event will keep dropping events until indexer congestion is remedied. Check disk space and other issues that may cause indexer to block

The other day I received this error:

Applying indexing throttle for defaultdb\db because bucket has too many tsidx files, is your splunk-optimize working?

I have recently upgraded from 4.1.3 to 4.1.5. There was no immediate change but I did start using FSChange to monitor some directories.

I removed FSChange stanzas that I added from the inputs.conf and restarted and I am still having the issue, though the warning moved back to the second error.

In splunkd.log I see:

10-15-2010 08:20:18.131 ERROR DispatchCommand - Failed to start the search process.  
10-15-2010 08:20:18.162 WARN  DispatchCommand - The system is approaching the maximum number of historical searches that can be run concurrently. current=7 maximum=8  
10-15-2010 08:20:18.193 ERROR DispatchCommand - Failed to start the search process.  
10-15-2010 08:20:19.850 ERROR DispatchCommand - The maximum number of historical concurrent system-wide searches has been reached. current=8 maximum=8 Search not executed! SearchId=scheduler__nobody__windows_d2luX2V2ZW50bG9nX2NvdW50X3N1bV9pbmRleA_at_1287148800_967218771  
10-15-2010 08:20:19.896 ERROR SearchScheduler - The maximum number of historical concurrent system-wide searches has been reached. current=8 maximum=8 Search not executed!   SearchId=scheduler__nobody__windows_d2luX2V2ZW50bG9nX2NvdW50X3N1bV9pbmRleA_at_1287148800_967218771  
10-15-2010 08:20:23.193 WARN  timeinvertedIndex - splunk-optimize failed to start for index D:\Splunk_Data\var\defaultdb\db\hot_v1_16 : The session was canceled.  
10-15-2010 08:20:23.193 WARN  timeinvertedIndex - splunk-optimize failed to start for index D:\Splunk_Data\var\defaultdb\db\hot_v1_19 : The session was canceled.  

I am not sure if it is related. Perhaps with all my alerts that run at various intervals (10 min, 15 min, 20 min, 30 min) I am eclipsing 8. Would that cause the errors regarding not indexing?

I am currently not able to view any data for the last two days.

Thanks for any help!

Kevin