Backup/Restore: add support for external compressors and decompressors

[rsajwani]

Description

Replacement PR for #7978
Signed-off-by: Renan Rangel [email protected]

This change will allow us to use an external decompressor when available as opposed to the internal pgzip currently used. We ran some tests using pigz -d -c and we get a nice speed bump on decompression, around 30% or more faster decompressing when restoring from a backup in S3. While decompressing is still single-threaded in pigz, it uses separate threads for reading, writing and checksum, and it results in faster performance.

I wanted to get an initial feedback on this change, as we would like to also to plug our own compressor to use other encryption algorithms (like lz4 or zstd) with an external binary as this is a more flexible setup for users, but also work on the change to add built-in support for one of these compression algorithms.

Related Issue(s)

#7802

Checklist

• "Backport me!" label has been added if this change should be backported
• Tests were added or are not required
• Documentation was added or is not required - separate website PR is planned

Deployment Notes

[github-actions]

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[deepthi]

Looks like there was one place missed when flags were renamed in the original PR.