Dynamic Balancing combined with Hyperflow being introduced in R81.20 should reduce the incidence of the IPS Bypass being activated.
When IPS Bypass was first introduced in R70, firewalls had relatively few cores such as 2, 4, or even perhaps 8. If one of them got saturated by IPS it would cause a noticeable impact and it was appropriate in that scenario to disable IPS on all cores because there were so few of them. Unfortunately in todays world of 40+ core systems that methodology is completely inappropriate and essentially results in IPS being disabled on all cores all the time. What really needs to happen is the IPS Bypass feature averaging the utilization of all cores when deciding whether to go into bypass mode. Until that happens my recommendation is to leave the IPS Bypass feature off. See my other response on this topic here which has some content from one of my courses:
https://community.checkpoint.com/t5/Security-Gateways/IPS-Bypass-is-triggered-even-when-CPU-utilizat...
Gateway Performance Optimization R81.20 Course
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