When uploading large files the upload is split into multiple parts which are assembled at the end to create the final file. Previously we waited until each part was acknowledged before starting on the processing (i.e. compression, etc.) of the next part. Now, the request for each part is sent while processing continues and the response is read just before sending the request for the next part. This asynchronous method allows us to continue processing while the S3 server formulates a response. Testing from outside AWS in a high-bandwidth, low-latency environment showed a 35% improvement in the upload time of 1GB files. The time spent waiting for multipart notifications was reduced by ~300% (this measurement included the final part which is not uploaded asynchronously). There are still some possible improvements: 1) the creation of the multipart id could be made asynchronous when it looks like the upload will need to be multipart (this may incur cost if the upload turns out not to be multipart). 2) allow more than one async request (this will use more memory). A fair amount of refactoring was required to make the HTTP responses asynchronous. This may seem like overkill but having well-defined request, response, and session objects will also be advantageous for the upcoming HTTP server functionality. Another advantage is that the lifecycle of an HttpSession is better defined. We only want to reuse sessions that complete the request/response cycle successfully, otherwise we consider the session to be in a bad state and would prefer to start clean with a new one. Previously, this required complex notifications to mark a session as "successfully done". Now, ownership of the session is passed to the request and then the response and only returned to the client after a successful response. If an error occurs anywhere along the way the session will be automatically closed by the object destructor when the request/response object is freed (depending on which one currently owns the session).
pgBackRest
Building Documentation
General Builds
The pgBackRest documentation can output a variety of formats and target several platforms and PostgreSQL versions.
This will build all documentation with defaults:
./doc.pl
The user guide can be built for different platforms: centos6
, centos7
, and debian
. This will build the HTML user guide for CentOS/RHEL 7:
./doc.pl --out=html --include=user-guide --var=os-type=centos7
Documentation generation will build a cache of all executed statements and use the cache to build the documentation quickly if no executed statements have changed. This makes proofing text-only edits very fast, but sometimes it is useful to do a full build without using the cache:
./doc.pl --out=html --include=user-guide --var=os-type=centos6 --no-cache
Each os-type
has a default container image that will be used as a base for creating hosts. For centos6
/centos7
these defaults are generally fine, but for debian
it can be useful to change the image.
./doc.pl --out=html --include=user-guide --var=os-type=debian --var=os-image=debian:9
The following is a sample CentOS/RHEL 7 configuration that can be used for building the documentation.
# Install docker
sudo yum install -y yum-utils device-mapper-persistent-data lvm2
sudo yum-config-manager --add-repo https://download.docker.com/linux/centos/docker-ce.repo
sudo yum install -y docker-ce
sudo systemctl start docker
# Install tools
sudo yum install -y git wget
# Install latex (for building PDF)
sudo yum install -y texlive texlive-titlesec texlive-sectsty texlive-framed texlive-epstopdf ghostscript
# Install Perl modules that do not have CentOS packages via CPAN
sudo yum install -y yum cpanminus
sudo yum groupinstall -y "Development Tools" "Development Libraries"
sudo cpanm install --force XML::Checker::Parser
# Add documentation test user
sudo groupadd test
sudo adduser -gtest -n testdoc
sudo usermod -aG docker testdoc
Building with Packages
A user-specified package can be used when building the documentation. Since the documentation exercises most pgBackRest functionality this is a great way to smoke-test packages.
The package must be located within the pgBackRest repo and the specified path should be relative to the repository base. test/package
is a good default path to use.
Ubuntu 16.04:
./doc.pl --out=html --include=user-guide --no-cache --var=os-type=debian --var=os-image=ubuntu:16.04 --var=package=test/package/pgbackrest_2.08-0_amd64.deb
CentOS/RHEL 6:
./doc.pl --out=html --include=user-guide --no-cache --var=os-type=centos6 --var=package=test/package/pgbackrest-2.08-1.el6.x86_64.rpm
CentOS/RHEL 7:
./doc.pl --out=html --include=user-guide --no-cache --var=os-type=centos7 --var=package=test/package/pgbackrest-2.08-1.el7.x86_64.rpm
Packages can be built with test.pl
using the following configuration on top of the configuration given for building the documentation.
# Install recent git
sudo yum remove -y git
sudo yum install -y https://centos7.iuscommunity.org/ius-release.rpm
sudo yum install -y git2u-all
# Install Perl modules
sudo yum install -y perl-ExtUtils-ParseXS perl-ExtUtils-Embed perl-ExtUtils-MakeMaker perl-YAML-LibYAML
# Install dev libraries
sudo yum install -y libxml2-devel openssl-devel
# Add test user with sudo privileges
sudo adduser -gtest -n test
sudo usermod -aG docker test
sudo chmod 750 /home/test
sudo echo 'test ALL=(ALL) NOPASSWD: ALL' > /etc/sudoers.d/pgbackrest
# Add pgbackrest user required by tests
sudo adduser -gtest -n pgbackrest