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WD Red 6TB using SMR omg?

#1
I have a Qnap NAS and two WD Red 6TB hard disks. Trying to decide between static/thick/thin. I know there is a performance hit but quite like the flexibility of thin as would setup three volumes with snapshot on one and over-provision. I can't get a handle on how much the performance hit might be.

Also I was horrified to find out my WD Reds are using SMR. As I will setup as a RAID1 I wondered if thin would be a problem with these drives versus static. Cheers...
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#2
The only time you would potentially notice a performance difference would be in a 10GbE (or faster) Ethernet setup. Since you are limited to a 1GbE speeds, this will be your bottleneck. Either way, enabling caching will improve IOPS anyway. In a two bay box with multiple volumes thick volume would make sense. It is still possible to change afterwards. Differences between PMR and SMRNo matter an HDD adopts PMR or SMR technique, the read head only requires a narrower area of the written magnetic track. When new data are written sequentially on an SMR drive, the "shingled" magnetic tracks are still readable without affecting the reading performance.However, when the written data is to be edited or overwritten, the write head will not directly record the data on the existing magnetic track to avoid causing damage to the adjacent magnetic track. The edited data will be written on an empty area of the disk, while the original magnetic track with the old data will be kept unchanged temporarily. When the HDD is idle, it will take the reorganization mechanism where the old data bits on the original magnetic track will be erased automatically and become available again for any new data.In view of the reorganization mechanism mentioned above, the idle time is essential for an SMR drive. If an SMR drive undertakes long-time and intensive work of overwriting, it will not have enough idle time to reorganize the magnetic tracks, and there will be increasingly more such magnetic tracks being kept unchanged temporarily. In consequence, the SMR drive may need to write new data and reorganize the old magnetic track at the same time, resulting in an impact to some extent on the read/write performance. Vendors have developed firmware for SMR HDDs to optimize the reorganization mechanism in terms of the impact on read/write performance during overwriting tasks.Note:We recommend establishing a RAID on either all PMR drives or all SMR drives. If a RAID is established on both PMR and SMR drives, the overall read/write performance may be affected by the SMR ones during overwriting tasks. For details on RAID, please check out this article.Source: https://www.synology.com/en-us/knowledge...isk_drives
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