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nrobison · Wed Mar 05, 2003 2:25 pm

If you please, an explanation or two about what benefits (if any) an 8mb cache might offer for a standard small LAN file/print server box - I know I need lots of storage - 120 GB or more per logical disk, but can't convince myself that the cache will help keep the machine (probably a Tualatin PIII or slower Athlon XP) from bogging while managing multiple print tasks (a memory issue: 1gig expected), and responding to simultaneous file requests (a gross HD read/write speed issue).

Also, since only God can afford SCSI storage of that size (all workstations are SCSI at least for OS), are the WD Caviar line the most reliable (talking weekly backup here), or???

Thanks

Freon · Wed Mar 05, 2003 3:24 pm

What exactly are you serving? How many users? What is the size of files? How important are the files? Is this a pet project or a server for a company? How much total storage do you need? What kind of throughput do you expect?

nrobison · Wed Mar 05, 2003 3:35 pm

Right...ahem, sorry.

- Small business (professional office), significant graphics/printing production
- 2 users now, may grow to 5
- files from 20kb documents to 0.5 GB 3d vector models, inclusive
- files are vital - backup to firewire external HD or hot-remove IDE hard drives expected
- company server
- storage accumulation about 100 GB/year
- daily throughput estimated:

50 MB small (<100kB) files
1 GB medium (100kB-10MB) files
1 GB (average daily over 1 month) large (>10MB) files

Forge · Wed Mar 05, 2003 4:11 pm

8MB cache IDE tends to degradea bit more gracefully under large numbers of I/Os. Not as good as SCSI, IIRC, but better than the 2MB drives.

Buub · Wed Mar 05, 2003 4:32 pm

Actually, lots of cache is MORE important for a server.

And yes, you'll get even better performance (and lifetime) out of SCSI. But for the budget minded, a couple mirrored IDE drives is sufficient.

Wed Mar 05, 2003 4:45 pm

According to Storage Review's database, there's not much of a difference in performance between the 2MB and 8MB drives.
http://www.storagereview.com/comparison.html
Check out either the file server or web server "Drivemark" and look for the 100 and 120GB WD drives. The improvement is a few points at best and in some cases almost nothing at all.

Freon · Wed Mar 05, 2003 4:49 pm

With only 2-5 people, 2MB would be fine, but the 8MB drives really aren't that much more expensive. The WD 1200JB is only about $140 for OEM. The 8MB can't hurt anything and might make pulling up those 500MB files a little faster.

I tend to think printing and print serving won't touch your harddrive. A P3 1 GHz or better should be fine until you start running a database and a web server on top of it all.

I'd suggest also trying to setup your data on RAID1 or RAID5. You can do RAID1 in 2000/XP Pro or even RAID5 in 2000 Server. This will make it much easier on you when one of your IDE drives fail, which will happen. Software RAID5 isn't as bad on resources as you might think and doesn't waste as much space as RAID1.

yarbo · Thu Mar 06, 2003 1:37 am

I thought with hardware RAID 5, you take a big performance hit, so what kind of hit are we looking at with software RAID 5?

eckslax · Thu Mar 06, 2003 1:44 am

With such a small difference in price between the different cache sizes, it would be wise to get the 8MB version even if it only speeds things up a little. As you expand to more users or larger files, you will no doubt be grateful you spent a few extra dollars on it.

Buub · Thu Mar 06, 2003 4:02 pm

Software/hardware makes no difference with RAID-5, it's still the same storage algorithm, with the same write penalties.

RAID-5 is an inexpensive way to get fault tolerance.

RAID-1 is a good way to get fault-tolerance with a minimum of drives.

RAID-0 is a good way to lose all your data.

RAID-10 is a trade-off (over RAID-5) of choosing performance over cost. It's faster and more fault-tolerant, but you use n*2 drives instead of n+1.

Freon · Thu Mar 06, 2003 5:20 pm

The concern with RAID 5 is not so much read and write speed, but CPU usage.

Buub · Thu Mar 06, 2003 10:07 pm

True a software (or "host-RAID") implementation will use a lot more CPU for RAID-5 than for the other levels, because it has parity information to calculate for all the blocks going in and out.

But with today's CPUs, it might well be trivial for a high-end system. RAID-0, RAID-1 and RAID-10 are trivial for today's CPUs in software RAID.

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