To point zero of @Timothy_Hall ˋs statement and I totally agree with him here.
21800 is already shipped with enabled SMT feature in the BIOS.
Requires enabling of SMT feature only in '
cpconfig' (refer to "Enable SMT" section).
Check Point always recommends turning on SMT on appliances. However, under certain conditions it can also be disadvantageous (in your case QoS). To test SMT performance, you can check it from my point of view only with and without SMT.
The following statement is also often discussed:
SMT can increase message rate for multi process applications by having more logical cores. This increases the latency of a single process due to lower frequency of a single logical core when hyper-threading is enabled. This means interrupt processing of the NICs will be slower, load will be higher and packet rate will decrease. I think that's why Check Point doesn't recommend SMT in pure firewall and VPN mode. From my point of view, it only accelerates software balades. Therefore I use it if necessary, if many blades are activated. I'd like to discuss that with Check Point.
Small example with basic viewing:
This presentation is very simplified and should illustrate the issues. If SMT channel 2 uses all core resources with I/O operations, channel 1 must wait for the core resources. This can reduce the performance with enabled SMT. The same effect can occur with multi-queue and enabled SMT. The problem can be fixed by adjusting the Check Point affinity or disable SMT. What we see here, many Intel architecture issues can affect SMT and therefore the firewall performance.
There are also some cases in which SMT should not be used:
More for SMT see here in my article:
R80.x Performance Tuning Tip – SMT (Hyper Threading)
SMT (HyperThreading) Feature Guide
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