08-31-2020, 10:06 PM
(06-01-2020, 04:51 AM)zer0sig Wrote: Also, it's worth noting that rpi is just now releasing a 64-bit OS. I've been running a 64-bit armbian build on my PINE64 A+ since 2016 I believe.
Have you benchmarked 32-bit vs 64-bit on your various devices? I've run some benchmarks on the Pi3B+ and Pi4, 32-bit vs 64-bit, and 32-bit was consistently faster for most tasks (building things, browser benchmarks, etc - I didn't run spec because that's a pain to get running). A popular article some while ago demonstrated that for things that use 64-bit only instructions, 64-bit is (duh) faster, but in practical use, the gains aren't nearly so obvious. A 32-bit binary will almost always have a smaller memory footprint due to smaller pointers, and will therefore fit in cache better.
Supporting 8GB of physical RAM on 32-bit isn't a problem, because the Pi kernels ship with lpae mode - so they can address something like 40 or 44 bits of physical memory. There's still a per-process memory limit of 4GB (which, IIRC, is split 3G/1G on Linux), but that's not a huge limitation in practical use.
I totally get the desire to run a clean 64-bit OS, and I run one on my PBP, but it's far from clear that it's the better option for a memory limited device.
(08-25-2020, 05:44 AM)NickL Wrote: Has anyone here tried using zRAM to increase the usable memory for the system? It sounds like this would be a way to acceptably boost usable memory up into the 6 to 7GB range at the cost of some CPU overhead.
zram works, I personally prefer zswap but that's a bit of a point of contention around here. Both help a good bit.