TESTA Yes, mostly on shallow queue random 4k operations.
CPU power saving states allow idle cores to sleep (C1) or partially sleep (C2...). Activating a core from a sleeping or partially sleeping state takes enough time to impact SSD performance by up to 100 MBps. The changes in performance are most noticeable on shallow queue depth random 4K operations. Even headline sequential speeds can be impacted. For most users, disabling power saving states in the BIOS is not worth the slightly higher power consumption and reduced peak CPU performance that results. Peak CPU performance is reduced on Intel chips because of the way turbo boost is implemented: in order to turbo boost an active core, inactive cores are put to sleep in order to keep overall temperature down.
CPU power saving states allow idle cores to sleep (C1) or partially sleep (C2...). Activating a core from a sleeping or partially sleeping state takes enough time to impact SSD performance by up to 100 MBps. The changes in performance are most noticeable on shallow queue depth random 4K operations. Even headline sequential speeds can be impacted. For most users, disabling power saving states in the BIOS is not worth the slightly higher power consumption and reduced peak CPU performance that results. Peak CPU performance is reduced on Intel chips because of the way turbo boost is implemented: in order to turbo boost an active core, inactive cores are put to sleep in order to keep overall temperature down.
