From mboxrd@z Thu Jan 1 00:00:00 1970 MIME-Version: 1.0 In-Reply-To: References: <0cd144e079b9354209187e89b8a05836@quintile.net> <20180203201110.75A91156E80B@mail.bitblocks.com> From: "Digby R.S. Tarvin" Date: Sun, 4 Feb 2018 22:47:27 +0000 Message-ID: To: Fans of the OS Plan 9 from Bell Labs <9fans@9fans.net> Content-Type: multipart/alternative; boundary="94eb2c11c0c0e1ae4105646aba17" Subject: Re: [9fans] Is fossil/venti file system a good choice for SSD? Topicbox-Message-UUID: cc9893d4-ead9-11e9-9d60-3106f5b1d025 --94eb2c11c0c0e1ae4105646aba17 Content-Type: text/plain; charset="UTF-8" I am not familiar with the kirkwoods that you mentioned. Just to be clear, the USB drive I was describing is rotating media in an external enclosure, not a memory stick. Generally self powered, as powering a portable hard drive from USB with a RPi is asking for trouble. I have stopped buying flash memory devices from eBay and other vendors that are not well known with a reputation to protect - far to many counterfeits with less storage than the packaging claims on the market, and if you are unfortunate enough to try using them with the FAT or eFAT filesystem they are supplied with, data will eventually wrap around and destroy itself, probably after sufficient time that the seller (who may well be ignorant of why his/her stock was so cheap) is no longer around to complain to. A minor annoyance for me, but must be a lot of unhappy people losing irreplaceable photographs.. Fortunately for me, attempting for reformat with a Linux filesystem tends to fail on such devices, so I find out straight away and get to send them back and be refunded . I had to write a dedicated test program to demonstrate the subterfuge on the original filesystem - to prove that the reformatting was revealing an issue, not the source of it (as was often claimed). I also don't buy cheap USB stick. I like these https://www.kanguru.com/storage-accessories/kanguru-ss3.shtml because they have a real hardware write protect capability. Indispensable if you are going to be inserting them into other people's machines, but surprisingly uncommon. At over $200.00 for 256GB, they are are a bit upmarket, but I havn't had any problem with them yet. Anyway, so long as you are aware of the risks and limitations, flash memory devices are a useful technology, but not a complete replacement for rotating magnetic storage. On 4 February 2018 at 21:46, hiro <23hiro@gmail.com> wrote: > Hey, thanks for explaining. this usage is surprisingly valid. I have > some much much older kirkwoods for the same scenario. The benefit is: > gigabit ethernet, higher stability, case included, power supply > included (and no power problems as on rpi), lower price. > I boot them all from USB HDDs, but I see how flash would save more > power. Carry on! :) > > The main disagreement in this thread is calling all kinds of different > flash storage "SSD". common usage reserves this name for the sata or > more recent nvme disks that actually are much more stable, in my > understanding due to better controllers and their better wear leveling > algorithms. > > With sd cards and usb flash drives you are lucky if your 128GB stick > is not really 1GB flash with %1GB "wear leveling algorithm" where > after 1GB you rewrite your already saved data :D > > It's a low-end market with shitty margins, low quality controllers, > and in general too many counterfeits, even from good shops and big > retailers. so you can't even depend on the company/brand/product name. > > Privately I never had surprising problems with HDDs, I don't manage to > fill enough to notice the small risk in practice. > > All my old HDDs still work. They are only unused cause they got too > small to be worth spinning any more (waste of power). > > I project my SSDs will not fail before i get 10/40gbit connection to > my NAS. Till then my write wear will be limited by my low bandwidth > and high latency practical use cases. > > On 2/4/18, Digby R.S. Tarvin wrote: > > static web pages, remote login (so that I can power/depower other > hardware) > > and file remote file distribution (via scp) mostly. > > > > The main requirement is very low standby power consumption so that it can > > survive on batteries which are recharged using solar panels. > > > > Power consumption was the main reason for switching from laptops (~12W) > to > > Reaspberry Pis (1.2W).. > > > > The other advantage to the raspberry pi is that it is a cheap commodity > > item - if I have one misbehave, I can just swap it out and throw it away. > > However, other than failing SSD's, the raspberry Pis have proved very > > reliable. > > > > On 4 February 2018 at 09:52, hiro <23hiro@gmail.com> wrote: > > > >> > raspberry pi based servers > >> > >> what are you serving? > >> > >> > > > > --94eb2c11c0c0e1ae4105646aba17 Content-Type: text/html; charset="UTF-8" Content-Transfer-Encoding: quoted-printable
I am not familiar with the kirkwoods that you mentioned.
Just to be clear, the USB drive I was describing is rotat= ing media in an external enclosure, not a memory stick. Generally self powe= red, as powering a portable hard drive from USB with a RPi is asking for tr= ouble.

I have stopped buying flash memory devices = from eBay and other vendors that are not well known with a reputation to pr= otect - far to many counterfeits with less storage than the packaging claim= s on the market, and if you are unfortunate enough to try using them with t= he FAT or eFAT filesystem they are supplied with, data will eventually wrap= around and destroy itself, probably after sufficient time that the seller = (who may well be ignorant of why=C2=A0 his/her stock was so cheap) is no lo= nger around to complain to. A minor annoyance for me, but must be a lot of = unhappy people losing irreplaceable photographs.. Fortunately for me, attem= pting for reformat with a Linux filesystem tends to fail on such devices, s= o I find out straight away and get to send them back and be refunded . I ha= d to write a dedicated test program to demonstrate the subterfuge on the or= iginal filesystem - to prove that the reformatting was revealing an issue, = not the source of it (as was often claimed).

I als= o don't buy cheap USB stick.

I like these
https://www.kanguru.com/storage-accessories/kanguru-ss3.shtml
<= /div>
because they have a real hardware write protect capability. Indis= pensable if you are going to be inserting them into other people's mach= ines, but surprisingly uncommon.
At over $200.00=C2=A0 for 256GB,= they are are a bit upmarket, but I havn't had any problem with them ye= t.

Anyway, so long as you are aware of the risks a= nd limitations, flash memory devices are a useful technology, but not a com= plete replacement for rotating magnetic storage.

On 4 February 2018 at 21:46, hir= o <23hiro@gmail.com> wrote:
Hey, thanks for explaining. this usage is surprisingly valid. I have
some much much older kirkwoods for the same scenario. The benefit is:
gigabit ethernet, higher stability, case included, power supply
included (and no power problems as on rpi), lower price.
I boot them all from USB HDDs, but I see how flash would save more
power. Carry on! :)

The main disagreement in this thread is calling all kinds of different
flash storage "SSD". common usage reserves this name for the sata= or
more recent nvme disks that actually are much more stable, in my
understanding due to better controllers and their better wear leveling
algorithms.

With sd cards and usb flash drives you are lucky if your 128GB stick
is not really 1GB flash with %1GB "wear leveling algorithm" where=
after 1GB you rewrite your already saved data :D

It's a low-end market with shitty margins, low quality controllers,
and in general too many counterfeits, even from good shops and big
retailers. so you can't even depend on the company/brand/product name.<= br>
Privately I never had surprising problems with HDDs, I don't manage to<= br> fill enough to notice the small risk in practice.

All my old HDDs still work. They are only unused cause they got too
small to be worth spinning any more (waste of power).

I project my SSDs will not fail before i get 10/40gbit connection to
my NAS. Till then my write wear will be limited by my low bandwidth
and high latency practical use cases.

On 2/4/18, Digby R.S. Tarvin <digb= yt42@gmail.com> wrote:
> static web pages, remote login (so that I can power/depower other hard= ware)
> and file remote file distribution (via scp) mostly.
>
> The main requirement is very low standby power consumption so that it = can
> survive on batteries which are recharged using solar panels.
>
> Power consumption was the main reason for switching from laptops (~12W= ) to
> Reaspberry Pis (1.2W)..
>
> The other advantage to the raspberry pi is that it is a cheap commodit= y
> item - if I have one misbehave, I can just swap it out and throw it aw= ay.
> However, other than failing SSD's, the raspberry Pis have proved v= ery
> reliable.
>
> On 4 February 2018 at 09:52, hiro <23hiro@gmail.com> wrote:
>
>> > raspberry pi based servers
>>
>> what are you serving?
>>
>>
>


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