Inconstant write speeds.

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1 hour ago, kodyorris said:

Thanks! I set those drives to never spin down and that seemed to stop those errors. I also moved my cache drives to the on board Sata ports so now Trim is working. However, I still have the same results. The most recent speeds I am seeing is it will start at 116MB/s for a while until ram is full, then sits around 60-70MB/s. 

For speed issue, it is expected. Main reason should be Crucial M500 is a low-end SSD, low throughput when writing.


But Unraid also have its issue, storage performance not so good. In fact, you would found many post about that, most people will use mid-to-high SSD to overcome this. But if you upgrade to 10Gb network, same problem will occur again.


So, I don't use SSD / cache pool, , for the need of speed, I setup with large amount memory ( cache ) or use RAID0 pool which outside array.


On 7/6/2020 at 12:49 PM, kodyorris said:

Is there a way for the system to not use my ram as data cache?

In fact, no system will design in this way and problem not because it use memory as cache.

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ok thanks for the input. Ill look into upgrading my SSD's but I really don't think they are the problem. I swapped the cache drive for a SAS drive (as a test) that I know I can write to at about 230MB/s and I have the exact same results. Still using large zip folder to keep the write as sequential as possible.  Its frustration to have spent $ on unraid and hardware and only be able to write at such low speeds with or without cache. My reads sit around 106MB/s. My parity rebuild averages around 186MB/s.

Edited by kodyorris
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UPDATE! I have spent more testing booted into a windows bootcamp and now that TRIM is working properly the server reads/writes at 110MB/s all the time. This is great considering I just have a gigabit connection.  


So this means there must be something wrong with the OSX software because i'm obviously using the same hardware when booted with bootcamp. I read about disabling SMB signing in OSX and that did increase my performance to hover around 80MB/s. This still isn't perfect, but it is a improvement.  Anyone have any other OSX tweaks to improve performance now that Unraid seems to be under control? I haven't seen any new errors in my logs.

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