>
> i tested gigabit eth and 100 mbit ethernet cards on some systems and i
> noticed that bottleneck was generated between CPU and disk. Simply, you
> can see it yourself with helping copy/http get/write and time utility.I
> remember there are alot articles on the net regarding system
> bottlenecks. You can use google..:-)
>
Last time I said 'With help of 64-bits 1GB Network card and CAT5e cable
(I think 350 Mbps)'. This is wrong. The maximum speed of network part could only
up to is 1000/8 = 125 MB/s, minus 1MB overhead, 124 MB/s, not 350Mbps. Compare
with 266 MB/s on system bus (66MHz) and 48 - 96 MB/s on hard disk (7200rpm, 8.5 ms
average seek time with RAID-0), one can see that the disk is bottleneck if it is
data-intensive application, such as stock database.
>
> Also, cluster server doenst make your sytems more performance. It makes
> your systems single point of failure or fault tolerans.
>
> Hope this help..
> Ilker G.
>
> Hong Hsu wrote:
>
> > Chris, Many Thanks for your help AND point out my one typo.
> >
> > Actually I am thinking to add power to my system, either using Linux's SMP
> > and dual Intel Pentium 4 processors with a single system bus, OR clustering
> > two single processor Linux machines. With help of 64-bits 1GB Network card
> > and CAT5e cable (I think 350 Mbps), network part doesn't seem a bottleneck.
> > But I not sure which approach has better performance.
> >
> > Thanks again,
> > -Hong
> >
> >
> > "Christopher P Wright " wrote:
> >
> >
> >>>I have general questions regarding a typical Linux system's speed and
> >>>wonder this is right place to ask these questions. If this is not, Could
> >>>someone point out which group I can post.
> >>>
> >>probably not the best place, but i know of nowhere else.
> >>
> >>
> >>>With following typical components on a motherboard:
> >>> 512 MB 10K RPM DRAM,
> >>> Intel 850 chipset with 64-bits Data bus width and 400MHz Data Rate,
> >>> 32-bit/64-bit PCI 2.10 bus (33MHz/66MHz)
> >>> 20 GB Hard Drive
> >>>
> >>i think the 10k rpm goes with the harddrive, as dram doesn't rotate =)
> >>
> >>
> >>> Does Intel 850's 400MHz data rate fully used or not on 66MHz bus
> >>>speed? As speed of these components are measured by rates, I am
> >>>wondering how one can evaluate the system's speed roughly in terms of
> >>>using MB/sec so that one can see potential bottleneck or trend of
> >>>improvement. On Windows, using PCMark2002 benchmark software from
> >>>MadOnion.com, one can see 20-70 MB/sec on HD, 700 - 1,400 MB/sec on
> >>>DRAM. Is there a way one can measure system bus actual speed under
> >>>Linux or benchmark for DRAM, HD?
> >>>
> >>the 400Mhz is the dram clock. 66Mhz is standard pci (as is 33 sometimes).
> >>obviously, the 400Mhz would not be used fully from a 66Mhz feed. this is
> >>typical. (memory is faster than pci cards, etc).
> >>
> >>to test HD performance one can use 'hdparm -T -t'. that benchmarks hd
> >>speeds, and buffered reads (sort of memory bandwidth maybe?). im not sure
> >>of a tool to measure dram bandwidth directly, but i'm sure they exist
> >>somewhere. be sure to enable dma on the harddrive before you benchmark
> >>it, or the speeds will be worse. ( 'hdparm -d1 [device]' )
> >>
> >>
> >>>In addition, if I like to add a 1GB Network Interface Card for
> >>>clustering two same machines, should I add a 32-bit NIC card or 64-bit
> >>>NIC in terms of performance, and why?
> >>>
> >>64bit would generally be able to transfer data to/from the system twice
> >>as fast as a 32bit card, simply because it transfers twice as many bits
> >>per cycle. i think 64 bit may be clocked higher (the 66mhz) than the 32
> >>bit (33 mhz???) but i'm foggy on pci specs in that regard, someone else
> >>probably knows far more in depth.
> >>
> >>ttyl
> >>chris
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