[Samba] Performance issues since upgrading to 3.X to 4.X

[Rowland penny]

On 20/07/2020 14:02, Dragoniade via samba wrote:
> Hello,
> I'm a bit desperate so I'm trying to seek help here.
>
> Many year ago, I built myself 2 file servers (5 disks enclosure for 
> data, 2 disks enclosure for the OS) on a computer.
> It was running on Debian 7.11 for years without an issue and I was 
> getting 75MB/95MB when transferring file from it to a Windows client, 
> all having a 1gbs network card.
> https://i.ibb.co/N618Z4W/Debian-7.png
>
> However, after upgrading to Debian 8 and more recently Debian 11, I 
> keep noticing a  huge performance drop.
> The near 100 MB drop to a roller coaster of between 25MB and 60 MB/S, 
> the average being 40 MB/S
>
>
> I've been googling trying various 'performance' tweak', but nothing 
> seem to work as expected.
> https://i.ibb.co/RPjbMKV/Debian-10-Tweaks.png
> https://i.ibb.co/mqwZtgR/Debian-10-No-Tweaks.png
>
> The latest bloc of 'performance' setting were those:
> # Settings to enhance performance:
> strict locking = no
> read raw = yes
> write raw = yes
> oplocks = yes
> max xmit = 65535
> deadtime = 15
> getwd cache = yes
> socket options = TCP_NODELAY SO_SNDBUF=128480 SO_RCVBUF=128480
> max protocol = SMB2
> # End of performance section
>
>
> I've also tried an empty smb.conf file to fallback to default. Nothing 
> seem to work.
>
> Spec of the current machine:
> CPU: Intel(R) Core(TM)2 CPU 6600 @ 2.40GHz
> RAM: 2 GB
> Ethernet controller: Qualcomm Atheros AR8121/AR8113/AR8114 Gigabit or 
> Fast Ethernet (rev b0)
> SATA controller: Marvell Technology Group Ltd. Device 9215 (rev 11)
>
> I know this isn't my machine though, as I can rsync at the same speed 
> on both version of the OS.
> Debian 7
> sent 7,962 bytes received 4,467,150,861 bytes 81,966,216.94 bytes/sec
> total size is 4,466,564,278 speedup is 1.00
>
> Debian 11
> sent 8,574 bytes received 4,467,697,711 bytes 80,499,212.34 bytes/sec
> total size is 4,466,564,278 speedup is 1.00
>
>
> Anyone have any idea why such a speed drop? What default config could 
> be triggering this drop?
> All point out to the upgrade from Samba 3 to Samba 4, the lastest 
> being tested being 4.9.5-Debian
> I'm only interested in the File sharing of Samba. I have no need for 
> any of the Active Directory addition added in Samba 4 that may have 
> introduced this performance hit.
>
> Any help on what to do to fix this would be greatly appreciated.
>
> Thanks
>
>
>
>
Can we see your entire smb.conf, not just part of it ?

Rowland