1) are your hdd tuned up look in your syslog for disk problems.

nope, HD is working fine. No reading errors, and hdparm shows

/dev/sda:
Timing buffered disk reads:  204 MB in  3.01 seconds =  67.71 MB/sec

2) socket options apparently shouldn't be used with Linux 2.6 kernels

Tried without them, it just made it worse. The only improvement I got happened when using the socked options I've mentioned on my last post.

3) switching off oplocks stops client side caching have you got oplocks on on the xp host also ??

I've disabled oplocks trying to get a better performance. Acctualy, I just forgot to set it back on, but it really made no difference in speed. Are you talking about enabling oplocks on Windows XP with the registry key HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\LanmanServer\Parameters\EnableOplocks ? Haven't tried. I'll have a look into it.

4) TCP window size on your XP host are they set to the highest possible ?

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Tcpip\Parameters\TcpWindowSize ? What is the highest value I can set here?

5) Realtek NIc are know to be poor in speed and reliability consider a better one.

First step to take. If it shows improvement, I'll take the rest of your suggestions.

Thanks for your inputs,

Giovani



--------------------------------------------------------------------------
Damien Dye BSC(hon)
IT and Telecommunications Engineer
Mckenna Group
Lawn Road Industrial Estate
Lawn Road
Carlton-in-Lindrick
Worksop
Nottinghamshire
United Kingdom
S81 9LB

Email  : [EMAIL PROTECTED]
Tel    : (44) 01909541414
Direct : (44) 01909541462
Fax    : (44) 01909541415
Web    : www.mckennagroup.co.uk

Company Registered in England, McKenna Precision Castings Ltd
Company Registration Number 1713320
Registered address Lawn Road, Carlton-in-Lindrick, Worksop, Notts, S81 9LB
--------------------------------------------------------------------------






-------- Original Message --------
Subject: [Samba] Samba + BDE and slow speed on reading (long) (06-Feb-2008 15:32)
From:    [EMAIL PROTECTED]
To:      [EMAIL PROTECTED]

Hello list.

I'm new here, and I'm joining because I'm having a problem wich I can't
figure out the solution myself. Here's what's happening:

A Samba 3.0.24 is serving files to seven Windows XP clients. Three of those

clients run an application with a BDE database. The problem is that when
running this application on Samba, it gets very, VERY slow, causing it to
hang. I have noticed also an unusual low speed when receiving files from
the
samba server over network. When sending files to the server, the speed is
OK. Since the databases used by that apllication have about 50Mb each, the
problem must be caused by that slow speed on receiving files from the
server.

I've twiked the configuration a bit, and came to this results:

socket options = SO_RCVBUF=65535 SO_SNDBUF=65535 TCP_NODELAY
IPTOS_LOWDELAY - Very slow on reading, fast when writing
socket options = TCP_NODELAY IPTOS_LOWDELAY - still slow on read, but a
little better. Fast when writing
socket options = TCP_NODELAY IPTOS_LOWDELAY SO_SNDBUF=32768 - significant
improvement when reading files, but the application still hangs due to the
slow speed. Fast when reading.
socket options = TCP_NODELAY IPTOS_LOWDELAY SO_SNDBUF=32768
SO_RCVBUF=32768 - same as above, but writing speed shows deterioration.

Other significant parameters:

   max connections = 50
   dos filetimes = yes
   max open files = 4000
   nt acl support = yes
   preserve case = yes
   strict locking = no
   deadtime = 15
   unix charset = iso8859-1
   display charset = cp850
   oplocks = no
   kernel oplocks = no
   level2 oplocks = no
  local master = yes
   os level = 64
   domain master = yes
   time server = yes
   preferred master = yes
   domain logons = yes
   name resolve order = wins bcast host lmhosts
   wins support = yes
   wins proxy = yes
   dns proxy = no


So, I went for socket options = TCP_NODELAY IPTOS_LOWDELAY SO_SNDBUF=32768
and got these results:

Copying a 45678592 bytes throug samba, it takes from 45 to 60 seconds to
transfer. The same file though FTP takes only 3.9 seconds. I know FTP is
the
fastest protocol and cannot be compared to samba, but still, that's a HUGE
difference.

As a desperate measure, I've copied the whole database to a XP machine,
shared the folder to the network, mapped it to the other stations, and the
application runs perfectly again.

Conclusion: there's definitely a problem when reading files from samba
server. It's not network related, since FTP is really fast, and when
serving
the database from XP, the speed is OK too. The server is a brand new Core 2

Duo E4500, 2GB RAM, 160 GB HD SATAII, NIC Realtek r8169 connected to a
DES-1008D Gigabit Switch. The distro in question is FC5 fully updated.

As a related topic, I've came across a situation (two times and couting)
when writing files to the samba server is painfully slow. On both cases,
setting SO_RCVBUF=1 has resolved the problem. I don't know why, but it did.

Both times, the server was connected to a D-Link DES-1024 switch. Switching

NIC's and cables had no effect, but SO_RCVBUF=1 solved it instantly. Could
it be related tho this version of samba and the problem I'm having now?

Any thoughts?

Thanks,

Giovani Moda

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