WRITELOG wait time is large while transaction log is put on Fusion IO

Hi experts,

Our users complain SAP on SQL becomes slow sometimes recently. I check wait

event and find WRITELOG become top 1 in wait events. This never happened

before. I use Perfmon to check Avg. disk sec/Write is zero(<0.001). It does

not seem to be a storage issue. What happened?<o:p></o:p>

By the way, I use SQL 2012 with AlwaysOn(Sync mode), HADR_SYNC_COMMIT = 2.58

and it seems to be ok. What is the Amount of outstanding log I/O limit in SQL

server 2012? ( Diagnosing Transaction Log Performance Issues and Limits of the Log Manager - Microsoft SQL Server Development Customer… )

•  

  --- Wait event since DB start ---

  
  

   

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  ---Wait event when system is slow ---

  PS:first row: wait event name

  second row: Total Wait Time(ms)

  third row: Total Wait Time(%)

  fourth row: Avg. wait. (micro sec)