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DeepComputing: Early Access Program for RISC-V Mainboard for Framework Laptop 13

(deepcomputing.io)
150 points sohkamyung | 6 comments | 13 Nov 24 22:07 UTC | HN request time: 0.404s | source | bottom
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v1ne ◴[13 Nov 24 22:55 UTC] No.42131132[source]▶
This JH7110 is from 2021. Some specs: https://www.cnx-software.com/2022/08/29/starfive-jh7110-risc...

1.5 GHz CPU core frequency, some old RISC-V cores while we're still waiting for cores with decent single-core performance to compete with modern desktop processors.

Sorry, but for me this board is dead in the water, unless you can't use ARM/x86 for political reasons.

replies(2): >>42131171 #>>42131448 #
0x457 ◴[13 Nov 24 23:00 UTC] No.42131171[source]▶
It's a dev board. Reason to buy it: you need a desktop that has RISC-V cpu inside.
replies(2): >>42131225 #>>42131356 #
adgjlsfhk1 ◴[13 Nov 24 23:07 UTC] No.42131225[source]▶
The problem is that it's a dev board that will likely be slower than QEMU, and is missing half of the Risc-V extensions that you want to test with. (and it supports a maximum of 8gb of ram, so good luck compiling LLVM on it)
replies(2): >>42131651 #>>42131656 #
1. snvzz ◴[14 Nov 24 00:04 UTC] No.42131651[source]▶
>good luck compiling LLVM on it

4 cores, thus 2GB/core. Plenty.

replies(3): >>42131949 #>>42133046 #>>42133315 #
2. AlotOfReading ◴[14 Nov 24 00:51 UTC] No.42131949[source]▶
I regularly get OOMs at 16 GB/core doing debug builds. LLVM is practically a memory stress test.
replies(1): >>42139276 #
3. CoastalCoder ◴[14 Nov 24 03:58 UTC] No.42133046[source]▶
I can't remember if LLVM has this problem specifically, but the linker step with debug info can really explode the memory use.

And unfortunately, that's even without build parallelism.

4. adgjlsfhk1 ◴[14 Nov 24 05:07 UTC] No.42133315[source]▶
make -j4 for LLVM requires about 36GB (I know because I tried with 32GB). 16 gb is almost enough to maybe build a debug build of LLVM without threading, but it will take a few hours on a chip that slow. With only 8gb, you are going to be absolutely trashing your swap (which at pcie gen 1x2 speeds will be pretty darn torturous). I'm guessing this system will take ~8 hours to build LLVM.
replies(1): >>42134024 #
5. brucehoult ◴[14 Nov 24 08:00 UTC] No.42134024[source]▶
Fortunately the LLVM build framework allows you to specify how many link steps can be done in parallel separately from the number of other things done in parallel.

Also, linkers other than GNU `ld` (or `gold` which is faster but used more RAM) use a lot less RAM e.g. `mold`, or even better LLVM's own `lld`.

6. 0x457 ◴[14 Nov 24 18:15 UTC] No.42139276[source]▶
Only if you use FatLTO. I've compiled LLVM many times with less memory.

GCC on the other hand is another story. On a machine that I was able to compiled LLVM (thanks swap), I couldn't even extract GCC source code.