adminsly
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?? slow hard drive
hi, i have been trying to find why a server is not giving me the speed i want, and i might find out that HDD are not fast enought.
first , it is a server with ms server 2003, 2 raid (one raid1 for C: 2x36G, and one raid5 for data 3X140G) i never mount my server with 2 raid like that, but thats the way i pick it up. the HDD are Fujitsu MAW3147NC and MAP3367NC scsi-3, i dont know if these were good to buy but i know in ws they are shit and slow.
does my server 2003 have a setting to change the way it give ressource to NIC or HDD , let me explain.
here the test i make, from a ws nic 1gig i transfert a folder(7Gig 16000 file) from server to ws it take aprox 12minute, if i transfert the same folder, on the server from D: to C: it take 12 minute. and in both case CPU usage is 10-15%, when i transfert from WS to server USAGE of nic is 15-20% (should it be 100%??) and another test i did is i start 6 ws to download the same folder, it take for ever on the ws and the server CPU usage was aprox 20% and nic usage was 35-45%, if i have 6 ws downloading fron server it should take all the bandwidht and should load the CPU more than 20% ???
thats how i came to think that my HDD are not fast enought.
let me know what you think !
thanks
sly
first , it is a server with ms server 2003, 2 raid (one raid1 for C: 2x36G, and one raid5 for data 3X140G) i never mount my server with 2 raid like that, but thats the way i pick it up. the HDD are Fujitsu MAW3147NC and MAP3367NC scsi-3, i dont know if these were good to buy but i know in ws they are shit and slow.
does my server 2003 have a setting to change the way it give ressource to NIC or HDD , let me explain.
here the test i make, from a ws nic 1gig i transfert a folder(7Gig 16000 file) from server to ws it take aprox 12minute, if i transfert the same folder, on the server from D: to C: it take 12 minute. and in both case CPU usage is 10-15%, when i transfert from WS to server USAGE of nic is 15-20% (should it be 100%??) and another test i did is i start 6 ws to download the same folder, it take for ever on the ws and the server CPU usage was aprox 20% and nic usage was 35-45%, if i have 6 ws downloading fron server it should take all the bandwidht and should load the CPU more than 20% ???
thats how i came to think that my HDD are not fast enought.
let me know what you think !
thanks
sly
ASKER
good question, there is a program to see what is in raid and it is adaptec, so this can mean that the 2 raid are HW. ?
Transferring 7GB in 12 minutes is not at all bad performance ... especially with 16,000 different files involved. (A single file of that size would transfer a lot quicker)
If you have 6 different workstations doing transfers at the same time from the same disk, then the disk is likely "thrashing" to access the data ... and this will signficantly slow down the average access time. This is likely what is happening when you initiate the transfers all at the same time. The CPU % isn't surprising ... it doesn't take much CPU to initiate disk transfers; and if the disk is thrashing it most likely simply can't keep the network fully loaded, which would explain the 35-40% NIC loading. Note that 35-40% loading on a 1GB network is still a very good data transfer rate ==> nearly 4 times the max capacity of a 100MB network. Also, the sustained transfer rate for your drives is at best 125MB/s ... which would fully load a GB NIC ==> with multiple files involved, and especially with multiple transfers that are likely slowing down the accesses, I think 40% loading is not bad at all.
Note also that when you are transferring from the workstations to the server, the limiting factor may very well be how fast the workstations' hard drives are ==> NOT the server's.
If you have 6 different workstations doing transfers at the same time from the same disk, then the disk is likely "thrashing" to access the data ... and this will signficantly slow down the average access time. This is likely what is happening when you initiate the transfers all at the same time. The CPU % isn't surprising ... it doesn't take much CPU to initiate disk transfers; and if the disk is thrashing it most likely simply can't keep the network fully loaded, which would explain the 35-40% NIC loading. Note that 35-40% loading on a 1GB network is still a very good data transfer rate ==> nearly 4 times the max capacity of a 100MB network. Also, the sustained transfer rate for your drives is at best 125MB/s ... which would fully load a GB NIC ==> with multiple files involved, and especially with multiple transfers that are likely slowing down the accesses, I think 40% loading is not bad at all.
Note also that when you are transferring from the workstations to the server, the limiting factor may very well be how fast the workstations' hard drives are ==> NOT the server's.
ASKER
the transfert i did test in from server to WS.
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ASKER
65t, all my ws have gigabyte nic in it.
OK, I missed that earlier.
Forced accept.
Computer101
EE Admin
Computer101
EE Admin
Max usable bandwidth should be 80% at least thats what my network guys tell.