ZFS Hangs

Thomas Sparrevohn Thomas.Sparrevohn at btinternet.com
Sun Nov 4 06:17:29 PST 2007


On Sunday 04 November 2007 08:48:17 Peter Schuller wrote:
> > For example, pkg_delete seems to be _extremely_ slow and ^T reports that
> > it is stuck waiting on zfs:(&zio->io_cv) for an unreasonable (IMO) amount
> > of time.
> 
> FWIW, I have seen pkg_install (and possibly other pkg_* tools) being extremely 
> slow seemingly as a result of the active set of files it touches exceededing 
> the amount cached. In particular I had this problem after converting to ZFS, 
> but prior to switching to amd64 and more RAM.
> 
> It would sit and churn on disk I/O forever, entirely seek bound. Tracing the 
> processes showed it traversing the package database over and over (presumably 
> recursively following dependencies or some such). So the same files were 
> touched any number of times. As a result, with too little cached, runtime 
> exploded (it took hours and hours upgrading my desktop using *binary* 
> pre-built packages because the larger packages with a lot of dependencies 
> would take forever to install and delete).
> 

It could be the machine has 4GB memory and is running amd64 - However I can reproduce it with 
vm.kmem_size_max=2147483648 and with the default - It is not only with pkg_install but seems 
randomly.

but you are correct pkg_create seems to use significant amount of time - but due to the issues I am seeing
with ZFS - I have not looked into why pkg_create takes so long even for very simple packages  



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