🚀 go-pugleaf

On 02/21/96, John Kheit wrote:

>Under most DOS benchmarks I get rediculous read/write performance
>reports.  My barracuda also gets around 6.7m/sec (and its not wide
>or anything)...  Under NeXTSTEP (i.e. Unix variant) and using IOzone
>(an excellent benchmark, don't know if it exists for other OS's)
>I get more accurate reports around 2m/sec.

>IOzone simulates real world read/writes, and is careful to make
>the test file big enough so there are no secondary memory caching
>effects.  I.E. if you have 32megs of RAM and you use a test file
>of only 8megs, odds are that significant portions of it will be
>cached by the system.

Whoa!  I agree that many benchmarks are way too easily fooled by cache and that 
IOZone is one of the better benchmarks when used with a large enough test file.  
(I also like IOStone too.)

However: 

a) Barracuda 2 and Barracuda 4 series CAN actually achieve close to 7 MB/second 
doing continuous reads/writes from certain zones.  Hook 'em up to an appropriate 
controller on an Amiga (which has really tiny OS/FS overhead) and you can almost 
achieve transfers at that rate even going through the filesystem in real world 
situations.  Of course, real world also involves some seeking but....  (And then 
there are the 12450W and the new 4LP and 8 Barracuda series which look like they 
can achieve close to 14 MB/second internal transfer rate from the media.)

b) NEXTSTEP sucks in terms of driver/file-system performance and in this case is 
negatively impacting the figures that are being reported rather than reporting 
them "accurately."   Case in point:  IOZone exists for many Unix variants.  Take 
an Intel box.  Install NeXTSTEP/fip.  Run IOZone.  Remove NeXTSTEP and install 
Linux, FreeBSD, NetBSD or another Unix (Solaris maybe?) on the same system.  Run 
IOZone and watch your numbers double.  I haven't quite ever been able to figure 
out if this is a filesystem or driver-system problem on NeXTSTEP (and no it 
doesn't seem to be a problem with any one particular driver.)

-- 
Christopher Wolf - WolfWare - cwolf@wolfware.com (NeXTmail & MIME accepted)
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