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From 230def3aec1e56c09fef3f75ce9545322f4268ae Mon Sep 17 00:00:00 2001
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From: "Richard W.M. Jones" <rjones@redhat.com>
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Date: Sun, 27 Oct 2013 14:59:39 +0000
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Subject: [PATCH] builder: Add a section on performance to the manual.
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(cherry picked from commit 2937c035958f84986e84c47df49f79d19c4b5b59)
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---
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builder/virt-builder.pod | 45 ++++++++++++++++++++++++++++++++++++++++++++-
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1 file changed, 44 insertions(+), 1 deletion(-)
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diff --git a/builder/virt-builder.pod b/builder/virt-builder.pod
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index 7768366..a603fcf 100644
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--- a/builder/virt-builder.pod
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+++ b/builder/virt-builder.pod
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@@ -1288,7 +1288,50 @@ etc are truly random when the guest boots.
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You should check digital signatures and not ignore any signing errors.
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-=head2 USER MODE LINUX
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+=head2 PERFORMANCE
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+
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+The most important aspect of getting good performance is caching.
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+Templates gets downloaded into the cache the first time they are used,
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+or if you use the I<--cache-all-templates> option. See L</CACHING>
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+above for further information.
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+
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+Packages required for the I<--install> option are downloaded using the
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+host network connection. Setting the C<http_proxy>, C<https_proxy>
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+and C<ftp_proxy> environment variables to point to a local web cache
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+may ensure they only need to be downloaded once. You can also try
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+using a local package repository, although this can be complex to set
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+up and varies according to which Linux distro you are trying to
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+install.
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+
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+=head3 Skipping virt-resize
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+
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+Virt-builder can skip the virt-resize step under certain conditions.
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+This makes virt-builder much faster. The conditions are:
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+
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+=over 4
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+
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+=item *
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+
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+the output must be a regular file (not a block device), B<and>
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+
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+=item *
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+
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+the user did B<not> use the I<--size> option, B<and>
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+
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+=item *
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+
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+the output format is the same as the template format (usually raw).
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+
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+=back
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+
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+=head3 pxzcat
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+
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+Virt-builder can use C<pxzcat> (parallel xzcat) if available to
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+uncompress the templates. The default is to use regular C<xzcat>
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+which is single-threaded. Currently this has to be compiled in,
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+ie. virt-builder will probably need to be recompiled to use pxzcat.
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+
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+=head3 User-Mode Linux
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You can use virt-builder with the User-Mode Linux (UML) backend. This
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may be faster when running virt-builder inside a virtual machine
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--
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1.8.3.1
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