LAN transfer rate?

[jtsnow]

Im doing drive image backups over a 100baseT LAN using Norton Ghost from a
PC P4 w/XP to a network storage device.
Looks like the transfer rate over LAN is about 25 Megbit/s and LAN shows 25%
utilization and CPU about 50%. Drive is only being accessed about 1/3 the
time so drive is not limiting the data transfer.

This is a small home LAN with 4 PCs, a NAS and a printer attached.

Is 25 Mbit/s about the best one can reasonably expect to get on a 100 baseT?
Even at that rate, a 44 Gig backup can take a few hours.

Are there ways to easily tweek the LAN to get significant transfer rate
performance improvements? Or is 25% utilization the best I should expect
on a 100mb/s LAN?

Any tips appreciated.

[Yousuf Khan]

jtsnow wrote: Im doing drive image backups over a 100baseT LAN using Norton Ghost from a PC P4 w/XP to a network storage device. Looks like the transfer rate over LAN is about 25 Megbit/s and LAN shows 25% utilization and CPU about 50%. Drive is only being accessed about 1/3 the time so drive is not limiting the data transfer. This is a small home LAN with 4 PCs, a NAS and a printer attached. Is 25 Mbit/s about the best one can reasonably expect to get on a 100 baseT? Even at that rate, a 44 Gig backup can take a few hours. Are there ways to easily tweek the LAN to get significant transfer rate performance improvements? Or is 25% utilization the best I should expect on a 100mb/s LAN? Any tips appreciated.

I've seen my own transfers top out at 12.5%, while I've seen some
servers transferring at upto 60% efficiency. I don't what causes it, it
could be driver efficiency or perhaps some ethernet chipsets have more
intelligence.

Yousuf Khan

[Bob Willard]

Yousuf Khan wrote: jtsnow wrote: Im doing drive image backups over a 100baseT LAN using Norton Ghost from a PC P4 w/XP to a network storage device. Looks like the transfer rate over LAN is about 25 Megbit/s and LAN shows 25% utilization and CPU about 50%. Drive is only being accessed about 1/3 the time so drive is not limiting the data transfer. This is a small home LAN with 4 PCs, a NAS and a printer attached. Is 25 Mbit/s about the best one can reasonably expect to get on a 100 baseT? Even at that rate, a 44 Gig backup can take a few hours. Are there ways to easily tweek the LAN to get significant transfer rate performance improvements? Or is 25% utilization the best I should expect on a 100mb/s LAN? Any tips appreciated. I've seen my own transfers top out at 12.5%, while I've seen some servers transferring at upto 60% efficiency. I don't what causes it, it could be driver efficiency or perhaps some ethernet chipsets have more intelligence. Yousuf Khan

25% is poor and 12.5% is pretty terrible. I just tried copying a large
(~1GB) file between a couple of XP PCs over a 100 Mb/s FDX net (with a
Linksys BEFW11S4 switch in the middle), using Explorer's drag'n'drop.
NetPerSec showed ~9.9 MB/s pushing the file, and ~9.1 MB/s pulling it
back; ~79% efficiency pushing and ~73% pulling.

I confirmed those transfer rates by stopwatch+calculator. And I repeated
the experiment with a somewhat faster far-end PC, using Explorer's CTRL-C
and CTRL-V, getting slightly better transfer rates: ~9.9 MB/s pushing,
and ~9.5 MB/s pulling; ~79% pushing and ~76% pulling.

Note that file transfer STRs seem to be much better in an all-XP workgroup
than in a mixed XP-W9x workgroup; my earlier results with a ~0.5GB file
on a XP-W9x 100 Mb/s FDX net were:

- Pushing on 98 from 98$ to XP$: 86 secs => 5.81 MB/s
- Pulling on 98 from XP$ to 98$: 82 secs => 6.10 MB/s
- Pulling on XP from 98$ to XP$: 159 secs => 3.14 MB/s
- Pushing on XP from XP$ to 98$: 236 secs => 2.19 MB/s

All these results were using network mapped drives.
--
Cheers, Bob

[Mike Scott]

jtsnow wrote: Im doing drive image backups over a 100baseT LAN using Norton Ghost from a PC P4 w/XP to a network storage device. Looks like the transfer rate over LAN is about 25 Megbit/s and LAN shows 25% utilization and CPU about 50%. Drive is only being accessed about 1/3 the time so drive is not limiting the data transfer. This is a small home LAN with 4 PCs, a NAS and a printer attached. Is 25 Mbit/s about the best one can reasonably expect to get on a 100 baseT? Even at that rate, a 44 Gig backup can take a few hours. Are there ways to easily tweek the LAN to get significant transfer rate performance improvements? Or is 25% utilization the best I should expect on a 100mb/s LAN? Any tips appreciated.
It may be totally irrelevant to your case, but firewall s/ware on my
machines has been observed to hit throughput by an order of magnitude.
Never did find out why.

[jtsnow]

ok...i can try turnig those off as an experiment

thx
"Mike Scott" <v.nin@1.scottsonline.org.uk> wrote in message
news:36s7hcF56n7o6U1@individual.net... jtsnow wrote: Im doing drive image backups over a 100baseT LAN using Norton Ghost from a PC P4 w/XP to a network storage device. Looks like the transfer rate over LAN is about 25 Megbit/s and LAN shows 25% utilization and CPU about 50%. Drive is only being accessed about 1/3 the time so drive is not limiting the data transfer. This is a small home LAN with 4 PCs, a NAS and a printer attached. Is 25 Mbit/s about the best one can reasonably expect to get on a 100 baseT? Even at that rate, a 44 Gig backup can take a few hours. Are there ways to easily tweek the LAN to get significant transfer rate performance improvements? Or is 25% utilization the best I should expect on a 100mb/s LAN? Any tips appreciated. It may be totally irrelevant to your case, but firewall s/ware on my machines has been observed to hit throughput by an order of magnitude. Never did find out why.

[jtsnow]

ok...thanks...im my situtation is ethernet comin in to a external USB on the
PC. I think thats the link slowin everything down. Just ethernet to
ethernet its very very fast....its the USB in on the external drive thats
the killer....i think

"Bob Willard" <BobwBSGS@TrashThis.comcast.net> wrote in message
news:e7CdnYYHSrY0VpXfRVn-rw@comcast.com... Yousuf Khan wrote: jtsnow wrote: Im doing drive image backups over a 100baseT LAN using Norton Ghost from a PC P4 w/XP to a network storage device. Looks like the transfer rate over LAN is about 25 Megbit/s and LAN shows 25% utilization and CPU about 50%. Drive is only being accessed about 1/3 the time so drive is not limiting the data transfer. This is a small home LAN with 4 PCs, a NAS and a printer attached. Is 25 Mbit/s about the best one can reasonably expect to get on a 100 baseT? Even at that rate, a 44 Gig backup can take a few hours. Are there ways to easily tweek the LAN to get significant transfer rate performance improvements? Or is 25% utilization the best I should expect on a 100mb/s LAN? Any tips appreciated. I've seen my own transfers top out at 12.5%, while I've seen some servers transferring at upto 60% efficiency. I don't what causes it, it could be driver efficiency or perhaps some ethernet chipsets have more intelligence. Yousuf Khan 25% is poor and 12.5% is pretty terrible. I just tried copying a large (~1GB) file between a couple of XP PCs over a 100 Mb/s FDX net (with a Linksys BEFW11S4 switch in the middle), using Explorer's drag'n'drop. NetPerSec showed ~9.9 MB/s pushing the file, and ~9.1 MB/s pulling it back; ~79% efficiency pushing and ~73% pulling. I confirmed those transfer rates by stopwatch+calculator. And I repeated the experiment with a somewhat faster far-end PC, using Explorer's CTRL-C and CTRL-V, getting slightly better transfer rates: ~9.9 MB/s pushing, and ~9.5 MB/s pulling; ~79% pushing and ~76% pulling. Note that file transfer STRs seem to be much better in an all-XP workgroup than in a mixed XP-W9x workgroup; my earlier results with a ~0.5GB file on a XP-W9x 100 Mb/s FDX net were: - Pushing on 98 from 98$ to XP$: 86 secs => 5.81 MB/s - Pulling on 98 from XP$ to 98$: 82 secs => 6.10 MB/s - Pulling on XP from 98$ to XP$: 159 secs => 3.14 MB/s - Pushing on XP from XP$ to 98$: 236 secs => 2.19 MB/s All these results were using network mapped drives. -- Cheers, Bob