On the page "Just released – RAIDiator 5.3.5 (ARM)" (http://www.readynas.com/?p=6412) from May 24 2012, you will find this in the release notes:
The following are changes since RAIDiator 5.3.4: New features and bug fixes ... 8. Allow user to customize Disk Spin Down power management settings. ...
Is this the solution that Netgear came up with to solve the Disk Spin Up problem? The issue was that the disk took a bit too long to spin up and was marked as broken causing a very long raid rebuild upon next reboot. I had terrible problems with this and was just about to return my ReadyNAS NV+ v2 when the update (5.3.5) was released. This update solved my problems but it took a while to understand how it was solved... The simple but not very sexy solution from Netgear was to by default disable disk spin down! And I have so far left this setting in default mode since I guess the actual problem is not solved? Or? The result is that that my 8 Seagate (ST3000DM001-9YN166) disks (2 x ReadyNas 4 disks Raid 5) are constantly spinned up and using more power than necessary and causing more heat = higher fan speed = more sound than necessary. Therefore I once again ask, is this the best solution Netgear could come up with?
Just made another post regarding clicking or ticking sound from the disks. Could this have to do with the fact that the disks are constantly running? http://www.readynas.com/forum/viewtopic.php?f=24&t=65363
There are no notes about such problems in the compatibility list. Just a broken link for ST3000DM001-9YN166 to some firmware update. I have downloaded the firmware update tool from Seagate but that requires that you demount the disks and connect them to a computer running the tool.
Anyone who tried running the ReadyNAS NV+ v2 with the "Disk Spin Down power management settings" set to something else than the default (disabled)?
I have the Readynas Duo v2 with the same Radiator firmware that you have on. I decided to turn the spin down on and so far it seems to be ok for me with my streaming, but I haven't fully tested it to tell you whether or not it's actually spinning down, but I haven't had any lag when playing a file 2 hours after leaving it with the spin down settings on 10 minutes.
Problem more or less solved! After some heavy search on google and reading many forum threads I have decided to leave the setting as default (disabled disk spin-down). It seems the energy saving from having disk spin-down enabled or not are small and when using RAID on a NAS there is a risk using spin-down and it takes some time waiting for spin-up to complete. I still wonder if the actual problem has been solved by Netgear or not, but I will continue having the disks running at all time. The constant temperature is around 40 degrees Celsius and rotation speed of the fan is around 1360 RPM. Reading some other forums I have confirmed that disk temperature has little or no impact on disk lifetime on modern disks. The only downside as I can see it is the sound generated by constant spinning disks and fan.
...I will continue having the disks running at all time... The only downside as I can see it is the sound generated by constant spinning disks and fan.
My ReadyNAS is nearby my workstation, and when I was using "Disk Spin Down" it would drive me nuts to note that disks would spin-down and then spin-up again immediately. Could not possibly be good for them to do this (a *lot*!) when they were warm to begin with. I surfed like mad and found that the responsible code (noflushd iirc) was suspect at best, and maybe not compatible w/each & every drive type.
In my case I instead Soft Power Off my ReadyNAS by schedule now, run it for only an hour a day and six hours on Monday when I do my backup of the RN itself.
In your case I'm sure you are making the right decision to just leave it run.
I ran my NV+ 24/365 for three years and put over 25,000 power on hours on the original 500GB disk. I had the second 500GB disk fail within the first month, but the replacement (same make and model) also ran for over 25,000 hours. Those two disks and two others I used to expand the volume are in other uses, one is the system drive on this PC. The drives were replaced with larger 1TB drives because I was running out of space. My primary NVX runs 24/7 and the backup uses disk spin down. Each unit has 2x3TB and 2x1TB drives, and one of the 1TB drives has over 16,000 hours. I have actually lost more drives in the one with disk spin down (2) than I have in the one that runs 24/7 (1).
Professionals have been arguing for decades whether it is better to leave the computer on and the drives spinning 24/7 or shut them down every night and deal with the wear and tear of the start up and shut down routines. Electricians have been arguing over whether it is better to leave fluorescent lights on 24/7 or turn them on and off, with some tests leaning towards leaving them on.
Professionals have been arguing for decades whether it is better to leave the computer on and the drives spinning 24/7...
Part of the question here is what do you mean by "better".
Leaving the drives spinning is the only option for servers that need to provide fast response 24x7. Since this is the case in almost all datacenters, the effects of spin down really haven't been researched much.
I think it is pretty obvious that you don't want to spin down/up the drives too frequently. Other than that, it is pretty much a matter of personal preference.
And my point is that it appears noflushd is not doing spindown correctly, or at least it didn't with my drives.
So my personal preference is to leave them spin, unless you can shut them down for 23 hours out of 24, as I'm doing with my NV+.
A perfectly reasonable choice. Obviously correct operation is more important than the relatively small power savings (and many users also have gadgets that don't handle the spin-up delay well).
I am doing something somewhat less conservative (spin down threshold of a couple hours). But I haven't seen your issue.
And my point is that it appears noflushd is not doing spindown correctly, or at least it didn't with my drives.
So my personal preference is to leave them spin, unless you can shut them down for 23 hours out of 24, as I'm doing with my NV+.
A perfectly reasonable choice. Obviously correct operation is more important than the relatively small power savings (and many users also have gadgets that don't handle the spin-up delay well).
I am doing something somewhat less conservative (spin down threshold of a couple hours). But I haven't seen your issue.
I was doing a bit of research myself on noflushd and came across this info and was wondering if this has anything to do with the problems people are having with spin down.
noflushd is a Linux daemon that monitors disk activity and spins down idle disks. It then blocks further writes to the disk to prevent it from spinning up again. Writes are cached and flushed to disk when the next read request triggers a spin-up.
KNOWN BUGS AND LIMITATIONS Journaling filesystems like ext3, reiserfs or xfs bypass the kernel's delayed write mechanisms. This amounts to lousy spindown times when working off such a partition. There's no workaround for this.
StephenB - I had more reference as to whether to shut down desktops at the end of the day and then cold boot the next morning as opposed to leaving them on overnight and letting the machine sleep. At one point at work there was so much stuff loading at boot that even on C2D desktops it took several minutes to boot. You could literally hit the power button, go get a cup of coffee and come back and still wait for the log on screen. In this situation, most users chose to leave them one overnight as it was just a few seconds for the PC to "wake up".
StephenB - I had more reference as to whether to shut down desktops at the end of the day and then cold boot the next morning as opposed to leaving them on overnight and letting the machine sleep. At one point at work there was so much stuff loading at boot that even on C2D desktops it took several minutes to boot. You could literally hit the power button, go get a cup of coffee and come back and still wait for the log on screen. In this situation, most users chose to leave them one overnight as it was just a few seconds for the PC to "wake up".
Yes.
I think there are four basic themes in the various posts on this particular topic:
(1) the potential impact of disk spin down on reliability/disk life. As far as I can see there is not a lot of data out there. But from what I have seen, I think it is prudent to set your spin-down threshold conservatively.
(2) the potential impact of disk spin down on NAS usability. That is what your example illustrates. Waiting for spin-up can be frustrating, and some devices and applications don't behave well when there is a spin-up delay. If I had one of those devices I would leave my disks spinning.
(3) Some users are more concerned about reducing their carbon footprint than the economics. Some of them are willing to invest a lot of time trying to sort out why their drives won't spin down as expected.
(4) Some users want to reduce acoustic noise from the NAS when it isn't in active use. Like the "green" users, some of them are willing to invest a lot of time trying to sort out why their drives won't spin down as expected.
KNOWN BUGS AND LIMITATIONS Journaling filesystems like ext3, reiserfs or xfs bypass the kernel's delayed write mechanisms. This amounts to lousy spindown times when working off such a partition. There's no workaround for this.
It seems to me that I found even scarier disclaimers in the noflushd docs than this, though I can't put my finger on the text atm. Suffice to say my own troubles with noflushd led me to avoid using spindown altogether.
Back off-topic :oops: regarding fluorescent lamps and PCs left ON 24/7, there's another angle on this that has to be accounted for in a commercial environment, which is not just energy usage but also energy usage. :wink: Namely that watts consumed also directly translates to BTUs produced into the space. The biggest heat producer in a commercial office building is the occupants, and next biggest is the lights! Not sure where computers are, but maybe these days a strong 3rd. Anyway you don't wanna have to cool-down the hot air produced by light fixtures 24/7 if occupancy is only e.g. 12/5. So you turn 'em off. Cooling is expensive, very expensive.
For those offices where the PCs take too long to boot, I'd be inclined to try Hibernation mode to see if that's an acceptable alternative to the users.
NOLED Community Add-on can be used to turn off the led lamps on NV/NV+ (viewtopic.php?f=47&t=20382) but there is no Add-on for V2 edition so far. I would really like to turn those led lamps off.
Maxblack - even more expensive is the replacement tubes and the union electricians wages to come and change them out periodically. In a large industrial plant setting that drives many more decisions than the cost of anything else.
Maxblack - even more expensive is the replacement tubes and the union electricians wages to come and change them out periodically. In a large industrial plant setting that drives many more decisions than the cost of anything else.
Not sure what implication you are drawing. however it is true that the cost of "relamping" is what is balanced against the cost of energy use. The US government advice says that if you won't be using the fluorescent lights for 15 minutes you should turn them off. (http://www.energysavers.gov/your_home/l ... opic=12280).
Anyway, our facilities have corridor lights on timers, and a couple years ago replaced the switches with motion-sensor versions that automatically turn off the lights in the offices if no motion has been detected for a while. So at least in our company there is no debate on turning off the lights.
The corresponding tradeoff for a NAS is balancing the power savings against the disk replacement costs. I haven't seen much definitive on this topic, though there are several researchers who have been looking at variations of Raid that allow some disks to spin down. For instance, concentrating frequently accessed data onto some of the disks can allow the other disks to spin down. One paper on this is here: http://www.eng.auburn.edu/~xqin/pubs/icpp10.pdf It is a bit surprising that there is so little information on what is suitable spin down threshold.
NOLED Community Add-on can be used to turn off the led lamps on NV/NV+ (viewtopic.php?f=47&t=20382) but there is no Add-on for V2 edition so far. I would really like to turn those led lamps off.
