GitHub user noxomix created a discussion: Sync-Mode (write_options.sync=on) 
extremly slow writes

Hey,  
I’m currently trying to run Kvrocks (2.14 via Docker) in durable mode 
(`rocksdb.write_options.sync=on`). I already tested it on four different 
servers: small VPS, high‑throughput VPS, and finally a dedicated server with 
NVMe.  

My configuration:
```yaml
bind 0.0.0.0
port 6666
rocksdb.write_options.sync yes
rocksdb.enable_pipelined_write yes
workers 8 # also tried 16, 32, 64
```

As far as I understand, RocksDB should be capable of handling a lot of writes, 
especially through its **group‑commit** features. There are several comparisons 
([like this 
one](https://tidesdb.com/articles/benchmark-analysis-tidesdb-v7-1-0-rocksdb-v10-7-5-full-sync/))
 that claim **100k+ writes per second** on a SATA SSD.  

For me, **without sync mode**, I can achieve with `redis-benchmark` around 
**45k wps**, but in **sync mode** I’m only getting **~1.6k wps** – it really 
gets worse. On my dedicated server, I’m now only getting about **1.3k wps** on 
a dedicated NVMe. I thought the VPS volumes were just too slow… but it turns 
out something else is limiting me, and I can’t figure out what exactly.  

I tried this 
[https://github.com/redis/memtier_benchmark](https://github.com/redis/memtier_benchmark),
 as well as `redis-benchmark`, and even a self‑written benchmark that does **8k 
op/s** on my localhost Redis, but barely **1k op/s** on my Kvrocks.  

---

Maybe anyone can give me a hint:  
What am I doing wrong?  
Is it just that **Kvrocks + sync mode** don’t play well together?  
Or is it just **one configuration option** that needs to be set?

Best Regards Theo

GitHub link: https://github.com/apache/kvrocks/discussions/3353

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