[Devel] Re: [PATCH 0/9] namespaces: Introduction

[Serge E. Hallyn]

Quoting Eric W. Biederman (ebiederm at xmission.com):
> "Serge E. Hallyn" <serue at us.ibm.com> writes:
> 
> > This patchset introduces a per-process utsname namespace.  These can
> > be used by openvz, vserver, and application migration to virtualize and
> > isolate utsname info (i.e. hostname).  More resources will follow, until
> > hopefully most or all vserver and openvz functionality can be implemented
> > by controlling resource namespaces from userspace.
> >
> > Previous utsname submissions placed a pointer to the utsname namespace
> > straight in the task_struct.  This patchset (and the last one) moves
> > it and the filesystem namespace pointer into struct nsproxy, which is
> > shared by processes sharing all namespaces.  The intent is to keep
> > the taskstruct smaller as the number of namespaces grows.
> 
> 
> Previously you mentioned:
> > BTW - a first set of comparison results showed nsproxy to have better
> > dbench and tbench throughput, and worse kernbench performance.  Which
> > may make sense given that nsproxy results in lower memory usage but
> > likely increased cache misses due to extra pointer dereference.
> 
> Is this still true?  Or did our final reference counting tweak fix
> the kernbench numbers?

I haven't checked that.  I'll start a new set of runs later this
morning, should get the results out saturday.

-serge