1.4 KiB
🔀 #192 - Revert #79
| Author | ikawrakow |
|---|---|
| State | ❌ Closed |
| Created | 2025-02-07 |
| Updated | 2025-02-08 |
Description
While testing potential improvements of IQ1_S_R4 quantization, I ran into NaNs while running a DeepSeek-Lite perplexity calculation. I did a grep -r on a folder with many big files while running the calculation and suddenly I got a NaN PPL. I repeated the calculation without doing anything else at the same time and the NaN did not happen. I then ran with 32 threads on a 16-core system and was able to reliably get a NaN at some random chunk.
This means there is a race.
The race was most likely introduced in #79 (avoid repeating already done quantizations of activations). I honestly do not understand why there could be a race, or even less do I understand why it would only happen for DeepSeek-Lite quantized with IQ1_S_R4. I have done countless runs since #79 and never observed anything suspicious.
Either way, this PR reverts #79. After doing so, there aren't any NaNs no matter how busy I make the system while running DeepSeek-Lite inference. Hopefully this will also fix the NaNs @saood06 gets with IQ1_S_R4 quantized DeepSeek-R1 (see discussion in #185).