SMP Performance (Was: Re: Are hardware vendors starting to bail ... )

[Tamouh H.]

> >>
> >> On Jul 13, 2006, at 9:22 AM, Danial Thom wrote:
> >>
> >>> Simply enabling SMP on a single processor system adds 20-25% 
> >>> overhead in freebsd 6.1. Again, readily admitted/accepted by the 
> >>> developers.
> >>> There is no way to recover that in efficiency, at least not for a 
> >>> long time.
> >>
> >> So don't enable SMP on a single cpu system.  Easy enough to avoid.
> >> Chad
> >
> > Why would anyone want to enable SMP on a single CPU system anyway.
> 
> Actually, I believe all the new boot disks / ISOs are all 
> SMP-enabled, so unless you build a custom kernel (some ppl do 
> just run GENERIC ... I'm not one, mind you), you could be 
> running an SMP-enabled kernel on a UP system without even 
> knowing it ...
> 
> ----
> Marc G. Fournier           Hub.Org Networking Services 
> (http://www.hub.org)
> Email . scrappy at hub.org                              MSN . 
> scrappy at hub.org
> Yahoo . yscrappy               Skype: hub.org        ICQ . 7615664

I have to put my two cents here:

1) I agree with few posters that FreeBSD performance have been lacking behind. I've reported few issues on performance list and many did. We offered few pre-production servers for performance testing, but the answer we keep getting is:

a. It is either your hardware sucks
b. your benchmark application sucks

2) Regarding SMP, few posts talked about disabling hyper-thread and SMP because it causes a performance degradation. On production hosting server, the experience was otherwise though. Without HT and SMP, the server would sky rocket in resource consumption. This has been tested on FBSD 5.4 i386

3) I'm also frustrated like many with the rapid advancement in release jumps. We barely started 5.x to conclude it does not live up to expectations, so now 6.x is suppoused to be the good version, yet 7.x is going to come out soon and probably in less than a year 6.x will be considered inadequate.

While I understand the development team is working hard to catch-up with technology and hats off to all the developers, why there is "in my opinion" no long term strategy for the base of the software.

Thank you,

Tamouh