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Best drive options?
WHEN IT COMES to external storage, Thunderbolt products come at premium cost, typically around twice the price of USB drives.What’s less apparent is the gap in performance; while Thunderbolt 3 SSDs readily exceed 1.5GB/s transfer speeds, and can reach 2.8GB/s, many USB equivalents struggle to reach 1GB/s, and some even fall below half that.
One reason is the confusion of opaque USB 3.x standards, against Thunderbolt’s minimum of two–lane PCIe 3.0, which guarantees at least 1.5GB/s. USB 3.x performance also varies more across different Mac models. Worryingly, some of the slowest are those with Apple’s latest M1 chips, with older Intel Macs often proving faster and more consistent in the face of USB connections.
For reliable speed and consistency, Thunderbolt is worth its premium.
When you see kernel_task climbing in Activity Monitor’s CPU listing it’s a sign your Mac needs cooling down.
> Warning sign in Activity Monitor
Sometimes I see kernel_task hogging the CPU in Activity Monitor on my MacBook Pro 15–inch 2019. After restarting, it’s fine again for a while, but reappears later. Why is this?
High CPU % load for kernel_task is the best sign that your Mac is getting too hot and needs to cool down. Often misinterpreted as the cause of problems, it’s actually part of your Mac’s defenses to keep it cool under thermal stress, and a warning sign. macOS monitors thermal sensors inside components, and the load imposed on its processor. When it suspects temperatures will rise, or they have already started increasing, macOS takes measures to increase cooling, such as blowing air over sensitive components using fans, and kernel_task occupies processor cores to block any runaway processes.