composer install is slow? How to speed up composer

[vagrant@localhost composer]$ ../composer_git/bin/composer install -vvv

Reading ./composer.json

Loading config file /home/vagrant/.composer/config.json

Loading config file /home/vagrant/.composer/auth.json

Loading config file ./composer.json

Executing command (CWD): git describe --exact-match --tags

Executing command (CWD): git branch --no-color --no-abbrev -v

Executing command (CWD): hg branch

Executing command (CWD): svn info --xml

Failed to initialize global composer: Composer could not find the config file: /home/vagrant/.composer/composer.json

To initialize a project, please create a composer.json file as described in the https://getcomposer.org/ "Getting Started" section

Loading composer repositories with package information

Downloading http://packagist.org/packages.json

Writing /home/vagrant/.composer/cache/repo/http---packagist.org/packages.json into cache

Installing dependencies (including require-dev)

Downloading http://packagist.org/p/provider-2013$8e290f3d47387c614761a9dc40a2ef6fb7dafb0cfe2264296e8fab2c6ee36bff.json

Writing /home/vagrant/.composer/cache/repo/http---packagist.org/p-provider-2013.json into cache

Downloading http://packagist.org/p/provider-2014$c0d0e03ec56584b3bf3148ac1565d89e789a57b90d72f83a7a54a55fbfc4f083.json

Writing /home/vagrant/.composer/cache/repo/http---packagist.org/p-provider-2014.json into cache

Downloading http://packagist.org/p/provider-2014-07$9b2d66a77e2f17ca1c18602419a2b53b00d42e0010d0a64fbbdcc1a01bbe092b.json

Writing /home/vagrant/.composer/cache/repo/http---packagist.org/p-provider-2014-07.json into cache

Downloading http://packagist.org/p/provider-2014-10$ed15097a7afa5a3f48b27f0ce38c5e3e8943514a0bdfd1898af31c9f8f913edb.json

Writing /home/vagrant/.composer/cache/repo/http---packagist.org/p-provider-2014-10.json into cache

Downloading http://packagist.org/p/provider-2015-01$3180dce46ea79fa77320185df239a62c07f6dbdeb21bc8ac6cd85b5d911a21ea.json

Writing /home/vagrant/.composer/cache/repo/http---packagist.org/p-provider-2015-01.json into cache

Downloading http://packagist.org/p/provider-2015-04$7e98f73b92b237ae4f6b07c8b8bd2e754357c86214cddf53cfafe8554b30f8b4.json

Writing /home/vagrant/.composer/cache/repo/http---packagist.org/p-provider-2015-04.json into cache

Downloading http://packagist.org/p/provider-archived$dfa1d92d2697fc375a1d522ab573634ee18807646f4abc322b6933157a07b829.json

Writing /home/vagrant/.composer/cache/repo/http---packagist.org/p-provider-archived.json into cache

Downloading http://packagist.org/p/provider-latest$115a50bcbcb32507b9b7b41a1d44b80ddd4848fb12cefee5769e9eb71769f7a8.json

Writing /home/vagrant/.composer/cache/repo/http---packagist.org/p-provider-latest.json into cache

Downloading http://packagist.org/p/monolog/monolog$c1954eb1d33e701ea323b97ff003a6495c79b138fe68a9087a9dce1d06e90ebc.json

Writing /home/vagrant/.composer/cache/repo/http---packagist.org/provider-monolog$monolog.json into cache

  - Installing monolog/monolog (1.0.0)

Downloading https://api.github.com/repos/Seldaek/monolog/zipball/433b98d4218c181bae01865901aac045585e8a1a

    Downloading: 100%

Writing /home/vagrant/.composer/cache/files/monolog/monolog/433b98d4218c181bae01865901aac045585e8a1a.zip into cache

    Extracting archive

Executing command (CWD): unzip '/vagrant/composer/vendor/monolog/monolog/2db4c7a59b236e77c15ff6a4f279a2c6' -d '/vagrant/composer/vendor/composer/abaad4e5' && chmod -R u+w '/vagrant/composer/vendor/composer/abaad4e5'

    REASON: Required by root: Install command rule (install monolog/monolog 1.0.0)

Writing lock file

Generating autoload files

(http://pkg.phpcomposer.com/repo/packagist/)[http://pkg.phpcomposer.com]

(http://comproxy.cn/repo/packagist)[https://phphub.org/topics/57]

(https://toran.reimu.io/repo/packagist/)[https://toran.reimu.io/]