vCPU requested = vCPU limit

In the first four tests, we deployed and ran our HammerDB test harness against sqlmi-01 through sqlmi-04, independently. As expected, we observed near linear scale of TPMs as the number of users increased. Also, the greatest TPMs were driven by the maximum 25 users when accessing the SQL MI with the highest requested compute resources. Memory utilization was never under pressure during the testing.

Figure 21.    Test 1-4 user count and TPM metrics vCPU Request = Limit

vCPU requested < vCPU limit

For these tests, we set the vCPU count requested to half the vCPU limit. In some cases, we observed increased performance with this configuration versus setting vCPU requested equal to limit. The TPM numbers were still within an acceptable range considering the resources that were allocated and the running workloads.

Figure 22.    Test 1-4 user count and TPM metrics vCPU Request < Limit

With the combined workload profile, we saw the greatest efficiency using a SQL MI with 2 requested vCPUs and a 4-vCPU limit. We considered it a best practice to maximize work with a reasonable core count even using a modern consumption-based pricing model.

Table 10.  SQL MI price and performance balance