Subject: Re: smbd dies under heavy transfers
To: Andy Ruhl <>
From: Chuck Swiger <>
List: netbsd-users
Date: 04/16/2007 13:46:51
Hi, Andy--

On Apr 16, 2007, at 1:23 PM, Andy Ruhl wrote:
> Anyone care to explain why this might be happening? I'm doing largely
> the same thing but with about 1000 fewer files, and I'm not having
> iTunes copy the files. It's using the files directly from the (NetBSD)
> samba server. I don't see this same problem.

If you're asking the Samba server to simply copy files from one  
location to another on the fileserver, it can do so without having to  
send the contents of all of those files to the client machine.

If you're using iTunes to process those files, it is probably reading  
them and then writing them back out, which involves a lot more data  
going back and forth in transit.

> It seems like iTunes should just be working serially, file by file,
> and that seems like it shouldn't be using so much memory?

iTunes is multithreaded, but I believe that iTunes attempts to  
serialize access to USB devices (ie, notably iPods).  However, it  
will perform some operations on your "song library" kept on disk in  
parallel, especially when doing certain one-time updates like trying  
to D/L album covers or figure out volume auto-leveling or gapless  
playback information.

> Maybe I'm missing something here, I don't really understand what
> iTunes is trying to do, or if Samba is trying to do something fancy.
> It just "works", and I haven't messed with it.

Samba does attempt to pre-read something like 32K or 64K of each file  
being accessed when a client opens it, but there is a tunable in  
smb.conf that you might want to play around with.  [1]

If you can gather more specific info into a reproducible test-case,  
please consider filing a bugreport against iTunes at https://


[1]: "read size", "large readwrite" parameters...