terrible write performance when almost full

this is an ext3/ext4 problem going back a few years, not really readynas specific. you can google ext4 fragmentation for lots of info

the root problem is the way ext4 allocates blocks gets less efficient when space is low, and as already noted above its best to keep 5-10% free space for best performance.

I know this isn't the answer you want, but if you are that low on space that performance is bad, then it is time to get bigger or more disks.

Thanks, I will take a look... I never really noticed this issue with older ext3 NAS's I have had. I live on boat, and am in the south pacific as we speak, so getting new hard drives will be a bit of a stretch for the time being. I am happy finally having RAID on my drives as electronics out here don't last long in the salt air...

buchhla wrote:
I am happy finally having RAID on my drives as electronics out here don't last long in the salt air...

A sealed USB cabinet should hold up longer then a fanned cabinet for multiple drives, at the loss of storage space, of course.
B!

yea, but I am worried about drive life without a fan as ambient temps get into 90's on a regular basis. The boat is also networked with Gb ethernet, so we can share the data between computers. and even cooler is we are 100% renewable using solar charging and LiFePO4 batteries for the boat... :)

buchhla wrote:
yea, but I am worried about drive life without a fan as ambient temps get into 90's on a regular basis.

I got that here at home, on a regular basis during the summer. 35c is the record this summer. A good sealed aluminum cabinet should have no troubles keeping up with that. But either way, you got the NAS, And now have to live with, or find a work around for the issues.
The workaround is fairly simple, leave 10% free space.

Cheers.
B!

buchhla wrote:
Thanks, I will take a look... I never really noticed this issue with older ext3 NAS's I have had. I live on boat, and am in the south pacific as we speak, so getting new hard drives will be a bit of a stretch for the time being. I am happy finally having RAID on my drives as electronics out here don't last long in the salt air...

Do you have an open slot? If so, you could try attaching silica gel packs to the unused drive tray. I suspect a lot of the damage is due to condensation, the gel packs might reduce or prevent that. Also, when the unit is running the temp is probably high enough to prevent most condensation, so if you are attached to external power you might keep the unit running.

I have always wanted to use an old but working refrigerator for keeping electronics cool and dust free.

TeknoJnky wrote:
I have always wanted to use an old but working refrigerator for keeping electronics cool and dust free.

I've wondered that myself - my backup NAS are in my attic, where it can get pretty hot. I keep the room cooled to 80 degrees F when I am not in it, but I suspect a small refrigerator could be more power efficient. However, they are designed for lower temperatures than are needed for electronics, and you have to modify it somehow to get the cables through.

But it is probably not practical for a boat, where power (and space) are much scarcer resources.

StephenB wrote:
If so, you could try attaching silica gel packs to the unused drive tray. I suspect a lot of the damage is due to condensation, the gel packs might reduce or prevent that. Also, when the unit is running the temp is probably high enough to prevent most condensation, so if you are attached to external power you might keep the unit running.

I'd ignore the silcagel. It's going to suck up all the water it can hold in just a few hours, days at most, if the humidity is high. After that, it's just useless. Leaving the units powerd on is a good idea tho. Even if there is a salt buildup, it's not as corrosive dry, as it is when it's collecting condensation.

Using a old refrigerator isn't cost effective. Worse yet, in the case of an air-conditioned room, the heat from the refrigerating unit is dumped in the room, adding to what has to be dealt with already.
A sealed cabinet, the only thing that can get degraded by moist air, and salts, are power and USB connectors. They can be replaced, either by replacing the whole cabinet, or the contacts them self, if need be. That should be the easy solution.
B!

well, obviously it wouldn't generate any more heat than a fridge in your kitchen generates... and using an old fridge may or may not be suitable for a boat, but in a home with a garage/attic/basement where it can run and not be heard or worried about the external heat generation, and you can put a UPS and switch inside and only have 2 cables going to/from while keeping multiple devices out of the normal environment.

Also, most fridges have thermostats, you can simply set it to the highest temp, which may not be good for food, but is sufficient to keep the devices cool enough, and save electricity compared to having to keep air conditioning at a lower temp or fridge at colder temp.

The idea is to use the fridge to protech/isolate the equipment from the environment.

I was going to use an old dorm fridge to store my readynas's in, but I gave it away to someone who needed it.