When to use ALS

You can enable ALS on any specified database that has at least one of the following performance issues, so long as your systems runs 4 or more online engines:

Heavy contention on the last log page.

You can tell that the last log page is under contention when the sp_sysmon output in the Task Management Report section shows a significantly high value. For example:

Table 3-2: Log page under contention
Task Management

per sec

per xact

count

% of total

Log Semaphore Contention

58.0

0.3

34801

73.1
Underutilized bandwidth in the log device.

**Table 3-2: Log page under contention**
Task Management	per sec	per xact	count	% of total
Log Semaphore Contention	58.0	0.3	34801	73.1

You should use ALS only when you identify a single database with high transaction requirements, since setting ALS for multiple database may cause unexpected variations in throughput and response times. If you want to configure ALS on multiple databases, first check that you] throughput and response times are satisfactory.