This may be a bit late, but for what it's worth, 4.8 -release as an ESXi 
4.1 client without any knob tweaking and pf running the default ruleset.
Haven't done anything with ESXi 3.5 though, so I'm not sure what to say 
on that front.

-----e@memnarch:/home $ uname -a
OpenBSD memnarch.sarlok.com 4.8 GENERIC#136 i386
-----e@memnarch:/home $ sudo dd if=/dev/zero of=/home/test.dat bs=16k 
count=32000
32000+0 records in
32000+0 records out
524288000 bytes transferred in 15.163 secs (34576797 bytes/sec)
-----e@memnarch:/home $ sudo dd of=/dev/null if=/home/test.dat bs=16k 
count=32000
32000+0 records in
32000+0 records out
524288000 bytes transferred in 13.937 secs (37617959 bytes/sec)
-----e@memnarch:/home $ mount | grep exports
172.16.100.250:/exports/home on /home type nfs (v3, udp, timeo=100, 
retrans=101)
-----e@memnarch:/home $ dmesg | head -10
OpenBSD 4.8 (GENERIC) #136: Mon Aug 16 09:06:23 MDT 2010
     deraadt@i386.openbsd.org:/usr/src/sys/arch/i386/compile/GENERIC
cpu0: Intel(R) Xeon(R) CPU E5504 @ 2.00GHz ("GenuineIntel" 686-class) 2 GHz
cpu0: 
FPU,V86,DE,PSE,TSC,MSR,PAE,MCE,CX8,APIC,SEP,MTRR,PGE,MCA,CMOV,PAT,PSE36,CFLUSH,DS,ACPI,MMX,FXSR,SSE,SSE2,SS,SSE3,SSSE3,SSE4.1,SSE4.2,POPCNT
real mem  = 536375296 (511MB)
avail mem = 517644288 (493MB)
mainbus0 at root
bios0 at mainbus0: AT/286+ BIOS, date 09/22/09, BIOS32 rev. 0 @ 0xfd780, 
SMBIOS rev. 2.4 @ 0xe0010 (98 entries)
bios0: vendor Phoenix Technologies LTD version "6.00" date 09/22/2009
bios0: VMware, Inc. VMware Virtual Platform


On 10-11-17 7:16 AM, Steven Surdock wrote:
quoted text
>> -----Original Message-----
>> From: owner-misc@openbsd.org [mailto:owner-misc@openbsd.org] On Behalf
> Of
>> Stuart Henderson
>> Subject: Re: ESXi client / NFS server performance
>>
>> On 2010-11-14, Steven Surdock<ssurdock@engineered-net.com>  wrote:
> ...
>>> where my problem lies.  Any pointers would be appreciated.
>>
>> When I ran ESXi 3.5 I found i/o was painfully slow, even with local
> disk
>> (and NFS performance with an OpenBSD server was appalling).
>> In general i/o performance in ESXi 4.1 seems a lot better, but I
> haven't
>> tried it with OpenBSD as NFS server yet.
>
> Thanks.  I've performed some other testing and found other clients work
> acceptably, so I'll assume it's an ESXi issue.  Iperf tops out at 300
> Mbps on my network, which sucks but it's better than the 50 Mbps NFS was
> doing.  I'll try upgrading to 4.1 this weekend and see if that helps.
>
> -Steve S.
>


-- 
http://blog.sarlok.com/
Sometimes all the left hand needs to know is where the right hand is, so 
it knows where to point the blame.