Drive access speed

[montyturbo]

I got a linux box set up as a router & Samba file server running Redhat 8.

Machine does its job almost perfectly apart from access speed to one of the drives which seems to be getting slower all the time.

This drive has the mountpoint '/home' and is used very heavily so I'm just wondering whether it is just in a mess or something and does it need the Linux equivelent of a Defrag! (is there such a tool and where do I find/how do I use it)

The drive has a 'directory' for each users own storage space and a 'directory' that is shared and all users can access. Lets make this simple, the drive has the following 'directories' for user access...

/home/john
/home/*****
/home/*****
/home/*****
/home/*****
/home/shared

(where ***** is a users name)

Now here's the wierd bit....access to all of these is not slow, the mountpoint that is shared is fine, access speed is great. Access speed to 2 of the 5 users space is the only problem, they are deadly slow! Other 3 users have no problems!

Now this makes no sense to me, hope someone here can make some sense of it and perhaps provide a little advice.....preferably in dummy fashion as I'm totally new to this Linux stuff (it took me over a week to get that Linux box set up and working properly)

Thnx in advance for any help/advice.

Cheers
John

[JohnT]

You say "one of the drives". How many drives do you have, and what are their specs?

[montyturbo]

Two drives in the system, both identical 20gb UDMA 66 Samsung drives (Model SV2011H)

The first drive contains everything except the mountpoint /home and the swap partition (1gb of it) these are both on the second drive.

Cheers

John

--------------

FULL SYSTEM SPEC (for linux box)

AMD K6/3 450 CPU
Gigabyte GA5-AX Motherboard (ALI Alladin V Chipset)
384 mb PC100 SDRAM
2 x Samsung 20gb HDD (set as primary master & slave)
Teac CD540 CDROM drive (Set as secondary master)
ATI Expert 2000 Pro 32mb AGP Graphics card
Creative PCI 128 Soundcard
Netvin 10/100 PCI Lan Card (Realtek Chipset)
USRobotics 56k Message modem

---------------------------

attached via Netvin 5 port hub are following winXP boxes....

AMD Athlon 2200XP
ABIT KG7 Raid Motherboard (Hybrid AMD 761/Via Chipset)
512mb PC2100 DDR
2 x Maxtor 40gb HDD ( Set as stripe array on raid controller)
Realsys 12x DVD Rom
Liteon 4012s CDRW drive
Nvidia Geforce4 4200Ti 128mb AGP card
Creative PCI 512 Soundcard
Netvin 10/100 Lan Card

Intel P4 1.7 CPU
Lex BN845R Motherboard (Intel 845D Chipset)
512mb PC2100 DDR
Samsung 40gb HDD (set as primary master)
Realsys 12x DVD Rom
Nvidia Geforce 4 MX440 64mb AGP Card
Creative PCI128 Soundcard
Netvin 10/100 PCI Lan Card

[JohnT]

I see you've got it striped, so there goes my first suggestion. Try setting the cdrom as the Primary slave(/dev/hdb) and the other HD as Secondary Master(/dev/hdc).
I've two HD's set up this way, non-striped and also different speeds, but very fast access to both.

[montyturbo]

Right, I think I can see where you are coming from here, but just one thing before I go swapping cables.....If this was a windoze machine I could simply swap the cables between cd rom and second hard drive.....this isn't windows though....so I assume I cant just swap the cables over and have the system work afterwards, is there anything I need to do before, during or after swapping the cables.

Sorry to be a pain in the rear....just cant have that system down!

Regards
John

[rdeschene2]

Maybe BEFORE you start swapping hard drive cables, use the du (see man du, checkout the --max-depth and -a switches) command to see if those users' home directories are just getting full.

You can "drill down" by directories using du to figure out WHERE all that disk space has gone. I have seen a similar thing when a partition got filled up due to an enormous Netscape cache.

When you do swap these cables you will have to change the entries in /etc/fstab to point the devices to the correct mount points.

[mdwatts]

Originally posted by JohnT
I see you've got it striped, so there goes my first suggestion. Try setting the cdrom as the Primary slave(/dev/hdb) and the other HD as Secondary Master(/dev/hdc).
I've two HD's set up this way, non-striped and also different speeds, but very fast access to both.

The striped drives are on the XP boxes.

The Linux/Samba box just has the 2-20gb Samsung drives.

As rdeschene2 suggested, first check to see how much space is being used in the problem /home directories.

Perhaps they have too many files/directories in their /home directories and that is slowing down the access speed.

Are all the /home directories set the same (using the same options etc.) in /etc/fstab and the Samba configuration?

[JohnT]

The striped drives are on the XP boxes.

Umm. I see that now. My bad.:D
What filesystem are you using, BTW?

[mdwatts]

Originally posted by JohnT
Umm. I see that now. My bad.:D
What filesystem are you using, BTW?

One more of those and I might have to report you. :p

I'm using ext3...

Oh you mean what filesystem is montyturbo using.

:D

[JohnT]

Oh you mean what filesystem is montyturbo using.

(In a small -medium nutshell) Yes.;)

[montyturbo]

Using ext3 filesystem,

Options for all users are set the same and there isn't really any difference between the number of files / amount of space used by the two 'problem' accounts compared to the other accounts.

Theres still over 9gb of total space on the drive too....

Oh, and the XP boxes are using NTFS file system.

Cheers

John

[JohnT]

Shooting in the dark , here, but post your /etc/fstab