RE: filmscanners: Second Hard Drive/Umax scanner
Because, (if my understanding is correct), the RAID card improves over normal SCSI error correction (1 bit) and ups this to 4 bit. It is nothing to do with RAID parity. Mark > -Original Message- > From: [EMAIL PROTECTED] > [mailto:[EMAIL PROTECTED]]On Behalf Of Bill Ross > Sent: 11 December 2000 20:50 > To: [EMAIL PROTECTED] > Subject: RE: filmscanners: Second Hard Drive/Umax scanner > > > ... The RAID port is populated with an Adaptec ARO1130U2 RAID > card on which hang two IBM Ultrastar 18ES 7200rpm 18GB drives > running a RAID0 (striped, no parity) array. > > ... Clearly, writing to SCSI outperforms IDE and has the added > advantage in that the error correction is better as the RAID > controller error correction is better than a standalone drive > > How could the RAID controller could improve error correction > w/out parity? > > Bill Ross
RE: filmscanners: Second Hard Drive/Umax scanner
... The RAID port is populated with an Adaptec ARO1130U2 RAID card on which hang two IBM Ultrastar 18ES 7200rpm 18GB drives running a RAID0 (striped, no parity) array. ... Clearly, writing to SCSI outperforms IDE and has the added advantage in that the error correction is better as the RAID controller error correction is better than a standalone drive How could the RAID controller could improve error correction w/out parity? Bill Ross
RE: filmscanners: Second Hard Drive/Umax scanner
> -Original Message- > From: [EMAIL PROTECTED] > [mailto:[EMAIL PROTECTED]]On Behalf Of Mike Kersenbrock > P.S - Magazines like P.C. Magazine has done benchmarking of > servers using IDE vs > SCSI disks, and I recall their conclusions to be that they > were very surprised to > find that it didn't make much difference in the actual > system performance. As a newbie to the list, this is my first post but maybe I can add some first hand experience and opinions to this debate... The system I run is as follows: The motherboard is dual PIII with built in U2W SCSI and RAID port. The RAID port is populated with an Adaptec ARO1130U2 RAID card on which hang two IBM Ultrastar 18ES 7200rpm 18GB drives running a RAID0 (striped, no parity) array. This array forms the basis of my main system drives and additionally, I have a ~30GB UDMA33 7200rpm IDE drive which I use as a dumping ground for files I only need to use once in a blue moon. The OS is NT4.0. Some example timings: Saving a 50MB cpt file to the SCSI drives takes about 5 seconds and to the IDE drive, about 10 seconds. Reading a 50MB cpt file from SCSI and IDE takes about 1 or 2 seconds. Clearly, writing to SCSI outperforms IDE and has the added advantage in that the error correction is better as the RAID controller error correction is better than a standalone drive (I should also point out that the IDE channel is dedicated to the harddrive - if you have another IDE drive on the same channel which is being accessed, the IDE timings will get a lot worse). You pays your money and makes your choice. I would always go for SCSI if the budget allows - but IDE offers way more space for your money. Don't know if that helped or not! Mark
Re: filmscanners: Second Hard Drive/Umax scanner
Rob Geraghty wrote: > > Bill Ross wrote: > >Just a thought - getting a small 10k rpm drive for current > >work plus a cheap large 5400 to park stuff might make for > >faster overall workflow at comparable price. > > >From what I've seen, 7200rpm drives are cheap enough that it's hardly worth > getting a 5400rpm drive. However as far as speed is concerned, the 16MB/s > limit of IDE is the pain - even if an IDE drive is 10K rpm it can't do sustained > transfers at over 16MB/s. That means (cache affects aside) a 30MB scan I thought that the UDMA/100 IDE interface was good for up to 100MB/s which according to reviews is much faster than the speed of the data coming off of the physical platters within the disk drives (and that even the older UDMA/66 is fast enough (66 MB/s) to be faster than the physical disk speed). I don't think "plain" IDE has been what drives have used for quite a few years. To get faster, I've read that one just needs to get faster (spin) disks with faster track access times to get the overall speed up, so it's not the IDE interface that's limiting factor, but the disk "underneath". Because high-end systems use SCSI, the high end fast-spin (> 7200 rpm) and fast access time disks (< 8ms )are SCSI ones. So for really fast speed one does need SCSI disks, but not because of the interface. There are some other theoretical advantages to SCSI in a multi-user server application but I don't know if they apply to the users in this newsgroup (not me anyway :-). Mike K. P.S - Magazines like P.C. Magazine has done benchmarking of servers using IDE vs SCSI disks, and I recall their conclusions to be that they were very surprised to find that it didn't make much difference in the actual system performance.
Re: filmscanners: Second Hard Drive/Umax scanner
Bill Ross wrote: >Just a thought - getting a small 10k rpm drive for current >work plus a cheap large 5400 to park stuff might make for >faster overall workflow at comparable price. >From what I've seen, 7200rpm drives are cheap enough that it's hardly worth getting a 5400rpm drive. However as far as speed is concerned, the 16MB/s limit of IDE is the pain - even if an IDE drive is 10K rpm it can't do sustained transfers at over 16MB/s. That means (cache affects aside) a 30MB scan takes 2 seconds to load or save, and a 50MB scan takes at least 3 seconds to load or save. A two drive IDE RAID array could nearly halve the times, and although they don't sound like much, having to wait a few seconds every time you save a file gets very tedious. Striping doesn't lose drive capacity - if your two drives are 20GB then your array is 40GB. However, a simple RAID stripe does NOT give the safety of parity. With 3 or more drives in an array you can have parity, which means that if one drive fails, no data is lost. Of course, parity also loses drive capacity. :) Also, for people whose motherboard may not support UDMA100, it gives you that without having to replace the motherboard. I just wish UDMA100 RAID was around when I was deciding on which motherboard to buy so I didn't waste the dollars on a board with built-in U2W SCSI. As with all these things, YMMV. As Bill suggested, 16MB/s may be just fine for many people. Hell, I've put up with 5400rpm for quite a while now - but since buying the film scanner it's getting annoying! Tony, I hope this isn't OT - I find the speed of loading and saving scans one of the most annoying aspects of using the film scanner. Rob Rob Geraghty [EMAIL PROTECTED] http://wordweb.com
Re: filmscanners: Second Hard Drive/Umax scanner
Just a thought - getting a small 10k rpm drive for current work plus a cheap large 5400 to park stuff might make for faster overall workflow at comparable price. Bill Ross
Re: filmscanners: Second Hard Drive/Umax scanner
> Does anyone have any experience with the Maxtor Diamond Max 81.9 (EIDE) > GB 5400 rpm hard drive? > Does anyone have any experience with the Maxtor Diamond Max 81.9 (EIDE) > GB 5400 rpm hard drive? I've had (still have) quite a few Maxtor drives and all have been good, apart from one 5Gb drive which died after ~2yrs. The 7200rpm versions are significantly faster, though not quite as quick as the IBM 7200rpm Deskstars, which is what I use now, for preference. Regards Tony Sleep http://www.halftone.co.uk - Online portfolio & exhibit; + film scanner info & comparisons
