Hi experts,<o:p></o:p>
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? ( http://blogs.msdn.com/b/sqlcat/archive/2013/09/10/diagnosing-transaction-log-performance-issues-and-limits-of-the-log-manager.aspx
)
--- Wait event since DB start ---
---Wait event when system is slow ---<o:p></o:p>
PS:
first row: wait event name
second row: Total Wait Time(ms)
third row: Total Wait Time(%)
fourth row: Avg. wait. (micro sec)