March 30, 20188 yr 50 minutes ago, Mat1926 said: If I am down to the last 10% of the available usable space?! I'm a "by needs" or, "by wants" sort, so if I was doing read and writes I'd probably be shopping around 20% space. But if you've hit 10% space I would say yeah buy more. Personally, I think of this as a user preference based on one's own requirements. Is there an optimized level to add more space to array? IDK. Edited March 30, 20188 yr by Jcloud
March 30, 20188 yr It's an impossible question for anyone other than the OP to answer since we don't know the rate at which the available space is being used up. If you haven't added any new files for the past six months then there's no pressing need to add more capacity. On the other hand, if you've gone from 20% free to 10% free in a week you might want to think about deleting some files you no longer need.
March 30, 20188 yr Author 19 hours ago, John_M said: It's an impossible question for anyone other than the OP to answer since we don't know the rate at which the available space is being used up. If you haven't added any new files for the past six months then there's no pressing need to add more capacity. On the other hand, if you've gone from 20% free to 10% free in a week you might want to think about deleting some files you no longer need. 21 hours ago, Jcloud said: I'm a "by needs" or, "by wants" sort, so if I was doing read and writes I'd probably be shopping around 20% space. But if you've hit 10% space I would say yeah buy more. Personally, I think of this as a user preference based on one's own requirements. Is there an optimized level to add more space to array? IDK. Sorry I was not clear enough. Before using unRaid, I used to have a couple of WD PR4100 raid systems, and the moment you hit the last 5% of the available space, then the system notifies you that you have to free more space since now this limited space hinders the performance of the system. It was raid 5... So I was curious if unRaid suffers from similar restrictions...
March 30, 20188 yr 31 minutes ago, Mat1926 said: So I was curious if unRaid suffers from similar restrictions... From a hardware standpoint a drive that is 5-10% filled will suffer some write speed due to fragmentation or edge of the platter and bit of increased latency because of longer travel distances (ie. the larger ring/circumferences).Does unRAID itself suffer from full disks? That I don't know, sorry.
March 30, 20188 yr 29 minutes ago, Jcloud said: Does unRAID itself suffer from full disks? That I don't know, sorry. I fill XFS disks up so that there's around 10 GB spare when they are used to hold data that will seldom, if ever, change. So once they are full I consider them to be essentially read-only. If you're using ReiserFS you really don't want to fill them as full because write performance is very poor when they are near to full, though read performance is still good. 10% of 74 TB is quite a lot of empty space.
March 31, 20188 yr I can confirm from personal (anecdotal) experience that my whole array seemed to slow down when I had a ReiserFS drive almost full. But I converted to XFS a few years ago, and I have absolutely filled up drives to where there might only have a few K left, and have never had a performance problem as a result. I will usually either only buy a drive when I truly need more space, or if an existing drive has failed. Right now I'm in the process of encrypting all my drives, so I'm going to have to make a drive purchase even though I have 3.6 TB free. Which pisses me off, because it probably would have taken me at least a year to fill up that space, but full disk encryption is an awesome feature, and I've got nowhere to put the files that need to be moved out of the way, so... it's time to order another drive. On the bright side once everything is said and done I should have about 12 TB free, which means I shouldn't have to buy another drive for years... Unless one fails...
March 31, 20188 yr 23 minutes ago, TSM said: I have absolutely filled up drives to where there might only have a few K left I don't recommend doing that. Over the years XFS has been updated as new releases of unRAID have been issued and with them the size of an empty file system has increased. In the early days of unRAID 6 an empty XFS filesystem occupied around 350 MB on my 5 TB disks. Now it occupies 5.5 GB. When I filled my disks almost to the brim and left only a few hundred megabytes free and this caused a lot of error messages when XFS was unable to modify the file systems after an update as there was insufficient free space. I now aim to leave around 10 GB free.
March 31, 20188 yr I have a number of 4TB ReiserFS drives filled to just over 1GB free. Write performance wasn't important since they store static content. But the big disadvantage is that I can't convert the disks to any other file system because there isn't enough space for the meta-data - most other FS needs more meta-data than RFS. So in the end, the drives will stay RFS until I replace them with 10+TB drives. As @John_M notes, XFS have increased the meta-data size several times as they have added bug fixes and functional improvements. So filling the drives too full can cause future issues.
March 31, 20188 yr Community Expert 6 hours ago, pwm said: I have a number of 4TB ReiserFS drives filled to just over 1GB free. Write performance wasn't important since they store static content. But the big disadvantage is that I can't convert the disks to any other file system because there isn't enough space for the meta-data - most other FS needs more meta-data than RFS. So in the end, the drives will stay RFS until I replace them with 10+TB drives. As @John_M notes, XFS have increased the meta-data size several times as they have added bug fixes and functional improvements. So filling the drives too full can cause future issues. Since the conversion process involves copying the data elsewhere and then reformatting the drive then you can still convert. It just might mean that not all the files go back on the drive.
April 1, 20188 yr 10 hours ago, itimpi said: Since the conversion process involves copying the data elsewhere and then reformatting the drive then you can still convert. It just might mean that not all the files go back on the drive. Correct, but I don't much like moving files around since I keep a registry of the exact content of every single disk and also if each file is stored according to configured backup policy.
April 4, 20188 yr On 3/31/2018 at 12:09 AM, John_M said: I don't recommend doing that. Over the years XFS has been updated as new releases of unRAID have been issued and with them the size of an empty file system has increased. In the early days of unRAID 6 an empty XFS filesystem occupied around 350 MB on my 5 TB disks. Now it occupies 5.5 GB. When I filled my disks almost to the brim and left only a few hundred megabytes free and this caused a lot of error messages when XFS was unable to modify the file systems after an update as there was insufficient free space. I now aim to leave around 10 GB free. Ummm... That may be true, but I'm not reformatting my drives every time I update the OS.
April 4, 20188 yr 1 hour ago, TSM said: Ummm... That may be true, but I'm not reformatting my drives every time I update the OS. The extra space may very well be needed if you get file system corruption and need to run XFS repair. That is one of the reasons the extra space is allocated now, so that the recovery tools can work.
April 4, 20188 yr 11 hours ago, TSM said: Ummm... That may be true, but I'm not reformatting my drives every time I update the OS. The file system can perform incremental updates when you update files. Some file systems can also perform incremental fs updates when first mounted with newer Linux driver. So reformat isn't the only operation that can increase the size of the meta data.
April 4, 20188 yr 8 hours ago, pwm said: Some file systems can also perform incremental fs updates when first mounted with newer Linux driver. That's precisely where I was seeing error messages when I had left too little free space for the metadata to expand into. Freeing up space and stopping/starting the array fixed the problem.
April 10, 20188 yr On 4/4/2018 at 5:25 PM, John_M said: That's precisely where I was seeing error messages when I had left too little free space for the metadata to expand into. Freeing up space and stopping/starting the array fixed the problem. OK, so does anyone have suggestions about how much space to leave?
April 10, 20188 yr 9 minutes ago, TSM said: OK, so does anyone have suggestions about how much space to leave? Like I said, I aim to leave around 10 GB free and so far it has been fine.
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