Being new to ReadyNAS there were various things I wanted to know. One of these was about the Defrag process and how long it takes to run.
Having trawled through the forums, one thing is apparent. Think carefully before carrying out a Defrag. It can take several hours or even several days on low performance systems. At it's worst, it can cause significant problems on a ReadyNAS system, especially if that system has very little free space, and Defrag has not been done before. The amount of time depends on how much data is used and also the capacity of the system, and whether you have snapshots and bitrot protection turned on. This is all covered elsewhere. It is NOT my intention to describe how Defrag works, but one thing I did discover was that Defrag can consume free space on disks. http://www.readynas.com/forum/viewtopic.php?f=11&t=79875#p451167.
I have now done two Defrags and intend to do them manually every few weeks, maybe months. The data below MAY be useful to new persons such as myself and help people with their expectations. So I suggest that those who are interested post their information in this post.
System ..... OS ....... RAID .... Disks ......... Total ........ Used ......... Defrag time ..... Comments RN516 ...... 6.2.2 .... 10 ....... 6 of 4 TB .... 10.90 TiB ... 1.59 TiB ..... 3 to 12 Mins .... With daily snapshots. RN516 ...... 6.2.2 .... 10 ....... 6 of 4 TB .... 10.90 TiB ... 1.66 TiB ..... 14 Mins .......... With daily snapshots. RN314 ...... 6.2.2 ..... 1 ....... 2 of 4 TB ...... 3.63 TiB ... 2.09 TiB ..... 4 Mins ........... With daily snapshots. RN312 ...... 6.2.2 ..... 1 ....... 2 of 2 TB ....... 1.8 TiB ... 1.00 TiB ..... 8 Mins ............ Without daily snapshots, and first time ever defrag for a home system (8,800 power on hours). Pro-6 ....... 6.2.3 ..... 5 ....... 3 of 3 TB ...... 5.45 TiB ... 2.03 TiB ..... 82 Mins .......... T1773, with snapshots - 1st run. Pro-6 ....... 6.2.3 ..... 5 ....... 3 of 3 TB ...... 5.45 TiB ... 2.14 TiB ..... 55 Mins .......... T1773, with snapshots - 2nd run. RN516 ...... 6.2.2 ..... 6 ....... 6 of 2 TB ...... 7.68 TiB ....????? TiB ..... 6 Mins ........... WD Red disks. Not used much. Run 1 year with 1 previous defrag.
PLEASE ADD YOUR DATA TO THIS POST especially if you have a different system or RAID setup.
I believe that a lot of ReadyNAS users have carried out Defrag, and mostly taking far more time than a few minutes. I am lucky (currently) that my system is at 15% capacity only. IMHO it is unwise to wait until your system is near full capacity and then do a Defrag.
Please note I am not a ReadyNAS expert, just a Newbie wishing to collate information for the good of all.
Almost a week has gone by with 77 views, and not one of you have any Defrag data that can be added? 😞 and 😮 The data can be old as it would still be relevant to give an idea of what is achievable or realistic. Please help provide reasonable expectations for those that have not yet carried out a Defrag.
How long a defrag will take will vary depending on how much data is on the system and the nature of that data, what settings you use on your shares and what else you are doing with the system during that time.
I agree, and hence the need to collect (even some limited data) on how long it will take. When I started I had absolutely no idea how long a defrag would take, and now I know that it can be minutes or possibly be even days. If we can possible provide evidence of when an incredibly long Defrag is likely, isn't it worth promulgating that info. If only to provide reassurance to users so they do not do 'something stupid' like power off. Surely knowledge is power 🙂
System ..... OS ....... RAID .... Disks ......... Total ........ Used ......... Defrag time ..... Comments RN314 ...... 6.2.2 .... 1 ....... 2 of 4 TB .... 3.63 TiB ... 2.09 TiB ..... 4 Mins .... With daily snapshots.
System ..... OS ....... RAID .... Disks ......... Total ........ Used ......... Defrag time ..... Comments RN312 ...... 6.2.2 .... 1 ....... 2 of 2 TB .... 1.8 TiB ...... 1.00 TiB ........ 8 Mins .......... Without daily snapshots, and first time ever defrag for a home system (8,800 power on hours).
OK, slightly off topic, but I thought since I was dealing with system tools, I'd give the Scrub tool a go as well, even though I have never used it before. I'm not sure what other people get, but after two hours of 'Scrubbing', it has only achieved 0.75% of the task :shock: - is this 'normal' ? I power off my RN312 nightly, so I'm turning Scrub off until I get some feedback. BTW, the NAS has not been doing other tasks during these two hours, and nobody has accessed it.
Nothing of note - both disks (WD20EFRX) have zero errors, and run normally at less than 27 dgrees C. I did have a bit of a trawl around the Forum looking for Scrub times, and a RN104 was quoted as 1GB per hour, but I would expect my RN312 to better that....
OK, slightly off topic, but I thought since I was dealing with system tools, I'd give the Scrub tool a go as well, even though I have never used it before. I'm not sure what other people get, but after two hours of 'Scrubbing', it has only achieved 0.75% of the task :shock: - is this 'normal' ? I power off my RN312 nightly, so I'm turning Scrub off until I get some feedback. BTW, the NAS has not been doing other tasks during these two hours, and nobody has accessed it.
BaJohn, I support your intent, as metrics are something I consider important, but I am unlikley to be adding my data anytime soon to your scrub post. If my rig could potentially take 200 hours to complete a scrub job, I'm just going to leave well enough alone :?
BaJohn, I support your intent, as metrics are something I consider important, but I am unlikley to be adding my data anytime soon to your scrub post. If my rig could potentially take 200 hours to complete a scrub job, I'm just going to leave well enough alone :?
What you don't know is if the percentage complete is actually accurate and your scrub would have completed a lot sooner.
Unfortunately I have only done the one scrub myself and my next is scheduled for a few weeks time, and other users either do not do scrubbing, or do not want to impart the information. The other scrub data supplied seems to be much quicker than mine, but this MAY be due to different OS, hardware, RAID configuration etc. Until more information can be gathered it is difficult to know what to expect, BUT I would think 200 hours (if that was what it turned out to be) would be abnormal. Incidentally, suggestions by 'the experts' indicate that scrubbing probably should be done every 3 months or so. If you are not going to do it, then there presumably will be consequences of making that choice.
What you don't know is if the percentage complete is actually accurate and your scrub would have completed a lot sooner. Incidentally, suggestions by 'the experts' indicate that scrubbing probably should be done every 3 months or so. If you are not going to do it, then there presumably will be consequences of making that choice.
Good point about the completion timing, but I just didn't want to leave the NAS powered on for (potentially) that amount of time, just to test. Obvioulsy, if there are consequences of NOT scrubbing periodically, then I will no doubt have to do it at some stage. For the moment, I'll just see what falls out of your 'experiment' 🙂
I've seen some posts in other places that suggest ~80 MB/s for ~5900 rpm drives is a reasonable estimate for scrubbing. Though it seems to be quite variable.
However, if it's correct then a scrub with 2x2TB Red drives should take about 7 hours, not 200.
Perhaps try running the experiment again, but let it keep going for 10-12 hours before canceling?
System ..... OS ....... RAID .... Disks ......... Total ........ Used ......... Defrag time ..... Comments Pro-6 ...... 6.2.3 .... 5 ....... 3 of 3 TB .... 5.45 TiB .... 2.03 TiB ..... 82 Mins .......... T1773, with snapshots
516 6 x 2tb WD red raid 6 defrag 6 minutes. It has been up for about a year. I may have run defrag once before. I do not use the NAS much for random writes, just storage
System ..... OS ....... RAID .... Disks ......... Total ........ Used ......... Defrag time ..... Comments Pro-6 ....... 6.2.3 ... 5 ......... 3 of 3 TB .... 5.45 TiB .... 2.14 TiB ..... 55 Mins ........... T1773, with snapshots
Hi, so I've done the defrag today after doing the balance on my system A (as per another balance thread)
System ..... OS ....... RAID .... Disks ......... Total ........ Used ......... Balance time ... Comments
A RN3220 ...... 6..2.4 .... 6.... 6 of 3 TB ...... 10.8 TB ... 5.4TB TB ..... 2 hours 20 mins....... First time running it, no VMs online so don't know impact
B RN3220 ...... 6..2.4 .... 10.... 6 of 3 TB ...... 8 TB ... 7 TB ..... 20 min. ........ Never done before
B RN3220 ...... 6..2.4 .... 10.... 6 of 3 TB ...... 8 TB ... 7 TB ..... 20 min. ........ Weekly schedule
We're due to upgrade the OS this week on both systems.
(I know this isn't a request area) I think it would be really useful if there was either a predicted or progress bar for defrag - unless I'm missing where it is?
(I know this isn't a request area) I think it would be really useful if there was either a predicted or progress bar for defrag - unless I'm missing where it is?
I've raised this myself with Netgear development.
btrfs itself provides progress information for scrub and balance. But defrag with btrfs is done file by file. So inserting progress information has to be done by the application. There is some concern that doing so would seriously increase the defrag running time.
It would still be helpful if there was at least a "defrag running" indication, or a display of the most recently defragged file.
Hi, here are some updated stats, we've spent time over new year putting in additional drives and changing the partitions, so we have a RAID10 partition that we use for iscsi connections and clustered storage. And a RAID1 partition that we use for backup so lots of data changing daily.
System ..... OS ....... RAID .... Disks ......... Total ........ Used ......... Balance time ... Comments
A RN3220 . 6...4.1 .... 10.... 6 of 3 TB ...... 8 TB .........6 TB ..... 30 min. ........ Weekly
A RN3220 . 6...4.1 .... ..1.... 2 of 3 TB ...... 3 TB ... ..... 2TB ..... 5 min. ........ Weekly
B RN3220 . 6...4.1 .... 10.... 6 of 3 TB ...... 8 TB ... .....6 TB ..... 2 min. ........ Weekly
B RN3220 . 6...4.1 .... ..1.... 2 of 3 TB ...... 3 TB ... .....1TB ..... 15 min. ........ Weekly
