I’m looking to buy another external FW drive (as a bootable backup)
and found one I like with FW 400, USB 2.0, eSATA but no FW 800.
Having only had access to FW 400 previously I’m wondering if it’s
wiser to get one with an 800 option as well now that I’ll soon have a
computer that supports it. It’s my understanding that there isn’t a
big real-world performance increase between 800 and 400, except on
paper.
Although I cannot comment on speed difference between FW 400 and FW 800, I am using FW 800 with a 1TB external dual drive for Time Machine b/u which works well in the background so far. Having some experience in the past with fw 400 “raid” enclosure I am quite skeptical about FW performance and would not recommend it as a main drive, but it does certainly work as a boot drive. I would think FW 800 will be more reliable than 400, but not sure.
I’m using fw800 with an external 1TB drive. In comparison fw400 feels SLOW.
Of course, that may just be my perception because I KNOW fw400 is slower. I usually have pretty large working graphics, which fw800 seems to handle more efficiently than 400. http://eshop.macsales.com/shop/ministackv3
On Mon, May 12, 2008 at 11:38 AM, Todd wrote:
I’m looking to buy another external FW drive (as a bootable backup)
and found one I like with FW 400, USB 2.0, eSATA but no FW 800.
Having only had access to FW 400 previously I’m wondering if it’s
wiser to get one with an 800 option as well now that I’ll soon have a
computer that supports it. It’s my understanding that there isn’t a
big real-world performance increase between 800 and 400, except on
paper.
Sometime around 12/5/08 (at 15:25 -0400) chuckamuck said:
Having some experience in the past with fw 400 “raid” enclosure I am
quite skeptical about FW performance
FireWire 800 is measurably faster than FireWire 400, particularly
with data bursts. But it is important to consider everything in the
chain. Using cheap, slow mechanisms will have an impact. And with
RAID enclosures, the RAID controller can make a massive different, as
will the particular level of RAID chosen.
All other things being equal, SATA is faster than FireWire 800, which
is faster than FireWire 400, which is faster than USB 2.0. (Sure, USB
2.0 is rated at 480kbps and FireWire 400 at 400kbps, but the
massively different architecture means it never gets near that
theoretical maximum in real-world use.)
RAID enclosures, the RAID controller can make a massive different, as
will the particular level of RAID chosen.
Sure, but I won’t ever trust a FW raid enclosure for server level usage ever again. I’ve lost too many files that way to ever be convinced.
All other things being equal, SATA is faster than FireWire 800, which
is faster than FireWire 400,…
External Sata is what i’m using at the moment for server b/u. Definately much faster than FW, and in my opinion more reliable. However, only the Pro level Macs can take advantage of this because they have open slots to add in a sata card, or the internal drive slots are also sata.
Sometime around 12/5/08 (at 19:13 -0400) chuckamuck said:
I won’t ever trust a FW raid enclosure for server level usage ever
again. I’ve lost too many files that way to ever be convinced.
Any files lost is too many. But while I absolutely agree that SATA
is the way to go for a server setup, I can’t agree that FireWire as a
technology is inherently less safe than SATA. There will be extra
factors involved.
Of course, it could well be that some FireWire RAID systems are less
critically specified or robustly built than the average eSATA RAID
box, as the typical user of those items is probably not as demanding.
But my connections and dealings with Sonnet, Wiebetech and other
respected drive and RAID system manufacturers and developers have
never left me feeling that FireWire as a technology is not as
trustworthy as SATA.
FIreWire is a communications/connection protocol. It does not
influence the way that data is written to the drive after it arrives
there, only the way that it is sent to and from the drive. In my
experience, if a packet of data is sent using FireWire, it will
arrive at the destination. There is quite a lot of error-checking
involved in this process, too.
Your mileage may vary, but that’s what I have seen using both 400 and
800 variants.
Now for server volumes, I stick to Fiber Channel myself…
(ducks for cover)
Walter
On May 13, 2008, at 12:41 PM, chuckamuck wrote:
I’m only concerned with the dangers of FW use as server volumes.
For any other use I have no problem with Firewire drives as I have
used many.
As I have said, I have no problem with Firewire as a technology. I use it all the time for stand alone storage. It’s when used in a server environment that the problem is apparent where multiple users access the same drive at the same time. Firewire 400 especially has a timing issue that fails in a striped raid situation with too many access tries at one time causing files to be left open or only partially written. Granted, this is partly to do with the FW box the drives are installed in since the hard drives themselves are not FW. I have not tried using a FW 800 based drive housing in this way, but i’m sure there is the potential for the same problem depending on load.
Sometime around 13/5/08 (at 13:10 -0400) chuckamuck said:
Firewire 400 especially has a timing issue that fails in a striped
raid situation with too many access tries at one time causing files
to be left open or only partially written.
I’d guess that this is just as likely to be down to bugs in the RAID
controller coding…
You don’t mention whether this is soft or hard RAID, either. I have
played around with soft RAID (I use it to make a mirror of my photos
on two disks inside my G4 MDD tower.) But for actual multi-user
access, I am “strictly traditional” and rely on hardware RAID 5,
connected to the server with Fiber Channel, and the server in
question is running a full Server version of Mac OS X and nothing else.
How many users are trying to access this server at a time? What OS is
it running? Is it also trying to be a workstation at the same time?
Walter
On May 13, 2008, at 2:05 PM, Keith Martin wrote:
Sometime around 13/5/08 (at 13:10 -0400) chuckamuck said:
Firewire 400 especially has a timing issue that fails in a striped
raid situation with too many access tries at one time causing files
to be left open or only partially written.
I’d guess that this is just as likely to be down to bugs in the RAID
controller coding…
You don’t mention whether this is soft or hard RAID, either.
OSX server, not workstation, softraid using Apple’s Disk Utility to setup.
But for actual multi-user
access, I am “strictly traditional” and rely on hardware RAID 5
I am in complete agreement with you here. Unfortunately, corporate wallets don’t always understand the technical issues (and therefore reason for large difference in cost) so go with the cheaper path…until they lose important files.
It’s not just the corporate wallets. I went the cheapest route I
could for many years, until a complete loss of an entire server
volume (and irreplaceable data) made me get a lot more serious about
this. I have spent many thousands to get where I am, but I rest
easier at night knowing that my data is in more than one drive, in
more than one place, and that it would take a serious disaster or a
lot of stupidity on my part (Are you sure you want to delete? Yes/No)
to make it not so.
Walter
On May 13, 2008, at 2:54 PM, chuckamuck wrote:
I am in complete agreement with you here. Unfortunately, corporate
wallets don’t always understand the technical issues (and therefore
reason for large difference in cost) so go with the cheaper
path…until they lose important files.
It’s not just the corporate wallets. I went the cheapest route I
could for many years, until a complete loss of an entire server
volume (and irreplaceable data) made me get a lot more serious about
this.
I know EXACTLY where you are coming from! This is the whole point I was skating around. Moral: DO NOT SKIMP on raid storage! Many sleepless nights could have been avoided…
