February 16, 20206 yr I've read many posts about this but can't figure it out how to fix it. New to Unraid... Server is setup with 2 512gb NVME Cache, 10gbit network through a 10gbit Switch. Transferring files from my Win10 PC is slow (for 10gb) 275MB/s max when transferring to Media share. Iperf tests show I can get 900MB/s plus. I'm thinking I setup something wrong because I found a post that said to try this: 1. Stop the array. 2. Go to Settings > Global Share Settings. 3. Turn Enable disk shares to On. 4. Start the array 5. Navigate to your server from the client machine using file explorer. 6. Double click the "cache" share. 7. Double click the share name you wish to write to. 8. Write a file to the share and note the performance. I tried the above, in the cache share I see my Media share, I transfer a file there and i get 10gbit speeds. But I don't know what i setup wrong. Global share set to YES for cache, Media share set to YES for use cache. Any Ideas?
February 16, 20206 yr Community Expert There is nothing set up wrong. When you enable disk drives you are setting up shares that correspond to physical drives, while the User Share System is a different view of your data that spans physical drives with the share name corresponding to a top level folder on the physical drives. For a share that has Use Cache=Yes, the file will first be written to cache (and thus visible under the ‘cache’ share in a folder corresponding to a User `share name) and will later be moved from cache to array and thus disappear from the ‘cache’ share. At that point it will be visible on one of the ‘diskX’ type physical drives. Throughout it will also be visible under the Media’ share which spans all the physical drives. the reason the post will have mentioned the procedure it does will be to allow you to bypass the User Share system and write directly to a physical drive. That way you by-pass the overheads of the User Share System and are going as fast as the cache drive (which is not part of the parity protected array) will allow.
February 16, 20206 yr Community Expert Like mentioned using user shares adds some overhead, though not always as pronounced, see this for example, sometimes enabling direct I/O (Settings -> Global Share Settings) helps with this.
February 16, 20206 yr Author 12 hours ago, itimpi said: There is nothing set up wrong. When you enable disk drives you are setting up shares that correspond to physical drives, while the User Share System is a different view of your data that spans physical drives with the share name corresponding to a top level folder on the physical drives. For a share that has Use Cache=Yes, the file will first be written to cache (and thus visible under the ‘cache’ share in a folder corresponding to a User `share name) and will later be moved from cache to array and thus disappear from the ‘cache’ share. At that point it will be visible on one of the ‘diskX’ type physical drives. Throughout it will also be visible under the Media’ share which spans all the physical drives. the reason the post will have mentioned the procedure it does will be to allow you to bypass the User Share system and write directly to a physical drive. That way you by-pass the overheads of the User Share System and are going as fast as the cache drive (which is not part of the parity protected array) will allow. I understand what you are saying, but isn't the point of having a cache to help speed transfers up (writes to fast cache first then mover moves it to array later)? I know the network and nvme cache is capable of the higher speeds. But with cache set to "Yes" it doesn't improve speed. If I set cache to "No" transfers are actually faster than "yes". That's seems odd to me I've tried direct I/O and reconstruct write and no change. Edited February 16, 20206 yr by LoST57 typo
February 16, 20206 yr 12 minutes ago, LoST57 said: I understand what you are saying, but isn't the point of having a cache to help speed transfers up (writes to fast cache first then mover moves it to array later)? I know the network and nvme cache is capable of the higher speeds. But with cache set to "Yes" it doesn't improve speed. If I set cache to "No" transfers are actually faster than "yes". That's seems odd to me I've tried direct I/O and reconstruct write and no change. That's why I have been telling people that with modern HDD and turbo write on, there's no need for a cache drive for a pure NAS use case. The point of having a cache drive is no longer to speed up write. It hasn't been the case really since docker and VM were introduced.
February 16, 20206 yr I read OP say if direct write to cache pool then speed normal but if write to share ( cache yes ) then speed slow ~275MB/s For 275MB/s, OP haven't clearly say does any read wrire on SSD and HDDs. How come a HDD can reach 275MB/s, so there must be something wrong because unclear info. But this may be true for FUSE layer. BTW, I haven't use share with cache so no much comments. Edited February 16, 20206 yr by Benson
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