Libguestfs - Aug 2017 - Re: read/write performance through mount point by guestmount

On Mon, Jul 31, 2017 at 06:52:28PM +0800, lampahome
wrote:
> if I mount through guestfs library in python or guestfish, the same
> condition happenes?
> 
> I mean the insane number of layers and the performance
No.  The layers are only present because guestmount uses FUSE.

libguestfs itself performs very well if you are careful to use it in
the correct way.

The architecture of libguestfs is described here:

  http://libguestfs.org/guestfs-internals.1.html#architecture

and we have tools for testing the performance of the virtio-serial
connection, qemu block layer and overhead of starting the appliance:

  https://github.com/libguestfs/libguestfs/tree/master/utils

and we have a page of tips on getting the best performance:

  http://libguestfs.org/guestfs-performance.1.html

Rich.

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2017-07-31 18:57 GMT+08:00 Richard W.M. Jones <rjones@redhat.com>:
> On Mon, Jul 31, 2017 at 06:52:28PM +0800, lampahome wrote:
> > if I mount through guestfs library in python or guestfish, the same
> > condition happenes?
> >
> > I mean the insane number of layers and the performance
>
> No.  The layers are only present because guestmount uses FUSE.
>
> libguestfs itself performs very well if you are careful to use it in
> the correct way.
>
> how about guestfish?
guestfish follows libguestfs or guestmount?

On Thu, Aug 03, 2017 at 05:37:39PM +0800, lampahome
wrote:
> 2017-07-31 18:57 GMT+08:00 Richard W.M. Jones <rjones@redhat.com>:
> 
> > On Mon, Jul 31, 2017 at 06:52:28PM +0800, lampahome wrote:
> > > if I mount through guestfs library in python or guestfish, the
same
> > > condition happenes?
> > >
> > > I mean the insane number of layers and the performance
> >
> > No.  The layers are only present because guestmount uses FUSE.
> >
> > libguestfs itself performs very well if you are careful to use it in
> > the correct way.
> >
> how about guestfish?
> guestfish follows libguestfs or guestmount?
guestfish is a thin wrapper around the libguestfs API.

I (again) strongly suggest that you read the documentation which
explains all this in great detail:

http://libguestfs.org/guestfs-internals.1.html#architecture
http://libguestfs.org/guestfish.1.html#description
http://libguestfs.org/guestfs-performance.1.html

Rich.

-- 
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