I didn't see anyone answer this. We noticed a tremendous slowdown of
our samba server the minute we put our first Vista client on it due to
IO. Turns out that by default, Vista has an indexing feature turned on
that sits there and loops continually indexing every file it can find.
So if you have mapped drives, and they have a lot of content...this user
had about 2gb in their home directory, it just murdered our samba
server. I'm no vista expert, but why you don't see a noticeable
performance hit when it indexes the local drive of the pc, I have no
idea, but when it was sitting on that mapped drive, it slowed the samba
server down for everyone. We turned that feature off on the Vista
machine, and the problem went away.
On Thu, 2007-10-18 at 09:57 -0500, samba@lists.rupa.com
wrote:> Issue: Vista reads slowly from a samba server. This appears to pop up
> periodically here and elsewhere.
>
> My samba.conf file has:
>
> [homes]
> ...
> vfs objects = readahead
>
> As suggested elsewhere.
>
> Writes are approximately 17-18MB/s which is acceptable. Reads are in
> the 8MB/s range which is appalingly slow. Using linux smbclient and
> windows XP clients I can read at 25+MB/s. I've enabled vfs objects
> readahead to get better performance in vista.
>
> The biggest difference I notice between vista and other clients is that
> the %iowait is MUCH higher than with the other clients. Logs show the
> readahead module being loaded but I have no idea if it is actually doing
> anything.
>
> [2007/10/18 08:24:48, 2] lib/module.c:do_smb_load_module(64)
> Module '/usr/lib/samba/vfs/readahead.so' loaded
>
>
> Server Config:
>
> CPU: Amd Athlon 2600+
> Ram: 1G
> Disk: software raid5 across 5 250G ide drives each on dedicated channels
> Kernel: Linux shakti 2.6.22 #1 SMP Wed Oct 17 15:32:01 CDT 2007 i686
> GNU/Linux
> Distro: debian etch
>
> Network: Gigabit (though cheapo)
>
> Any suggestions on where to go from here?
>
> iostat 5 output for the physical devices below:
>
> Using a new quad core running Vista client on gigabit
> - Reads at 8MB/s
>
> avg-cpu: %user %nice %system %iowait %steal %idle
> 2.81 0.00 9.62 73.95 0.00 13.63
>
> Device: tps Blk_read/s Blk_wrtn/s Blk_read Blk_wrtn
> hda 51.10 3033.27 20.84 15136 104
> hde 53.91 3028.46 16.03 15112 80
> hdg 49.90 2993.19 19.24 14936 96
> hdi 47.49 3036.47 6.41 15152 32
> hdk 49.30 2993.19 14.43 14936 72
>
>
> Using a midrange Laptop running Windows XP on gigabit
> - Reads at 20MB/s
>
> avg-cpu: %user %nice %system %iowait %steal %idle
> 3.80 0.00 23.80 14.20 0.00 58.20
>
> Device: tps Blk_read/s Blk_wrtn/s Blk_read Blk_wrtn
> hda 199.80 8366.40 25.60 41832 128
> hde 187.20 8380.80 8.00 41904 40
> hdg 190.80 8377.60 9.60 41888 48
> hdi 178.20 8376.00 16.00 41880 80
> hdk 188.80 8377.60 20.80 41888 104
>
>
> Using same host, smbclient, writing to a firewire drive
> - Reads at 26MB/s
>
> avg-cpu: %user %nice %system %iowait %steal %idle
> 7.58 0.00 38.92 30.74 0.00 22.75
>
> Device: tps Blk_read/s Blk_wrtn/s Blk_read Blk_wrtn
> hda 224.75 8693.01 20.76 43552 104
> hde 214.37 8713.77 12.77 43656 64
> hdg 212.97 8657.88 19.16 43376 96
> hdi 195.61 8629.14 23.95 43232 120
> hdk 197.01 8688.22 22.36 43528 112
>
> Using dd to firewire drive
> - Reads at 27MB/s
>
> avg-cpu: %user %nice %system %iowait %steal %idle
> 6.40 0.00 59.40 34.20 0.00 0.00
>
> Device: tps Blk_read/s Blk_wrtn/s Blk_read Blk_wrtn
> hda 310.80 12844.80 17.60 64224 88
> hde 317.80 12820.80 9.60 64104 48
> hdg 308.60 12779.20 14.40 63896 72
> hdi 294.00 12779.20 9.60 63896 48
> hdk 294.80 12796.80 19.20 63984 96
>