My comments on the updated HLS:
Section Notes, #4: Due to S9-S12 a lot of the core logics for more advanced features would be covered. From experience I'd say an DBA would like to be able to list available backups, so they can get the canonical name to use when restoring. I think we should provide a standard API for these services as well.
Section Specifying backup locations, paragraph 4; Prefix part is required, the rest is implementation specific to the BSM.
Section Specifying backup locations, paragraph 6; Due to the current limitation of the pluggable framework, each BSM _must_ register a differently named shared library for each prefix. Changing the general plugin framework is perhaps a too big task.
Section Native compression Support; Today it is better to leave compression to the storage. With the current trends in storage, a lot of vendors provide several means of efficient storage, ranging from normal 1:1, 2:1 (LZH) to 10-100:1 in de-duplicated storage. I really don't think MySQL backup kernel should be bothered with compressing with own algorithm, but leave it to the BSM. Requesting compression can obviously still be supported.
This also leads me to think about earlier discussion regarding encryption. Would MySQL backup kernel want to keep a fully working Key Management System (KMS) in order to use right keys. KMS is a very complex system, managing many keys such as current, not-in-use, expired, deleted etc. I again think it would be better to leave it to the BSM to implement encryption and KMS. If we look at NetBackup it supports compression, encryption on client side, but also de-duplication when going to OST storage. NetBackup also support KMS and AES256 encryption when storing on supported tape drives (LTO4 and Sun StorageTek T10000).
So S4 could potentially be followed be similar for encryption
All other parts of the HLS are good, and we should be able to proceed eventually with a LLD and implementation.
Best regards / Cordialement
From: Rafal.Somla@Sun.COM [mailto:Rafal.Somla@stripped]
Sent: 14. oktober 2009 14:35
To: Ingo Strüwing; Andreas Almroth
Cc: backup@stripped; Lars Thalmann
Subject: WL#5046 (PLuggable Storage Modules) - HLS updated
I have updated HLS. You might want to check if I accurately described the
alternatives which you suggested in your comments and if I haven't missed
something you consider important.
Next step for this project will be to finish HLS with design for error
reporting and string handling (Ingo already give some suggestions). Then we
should decide which alternatives we take and then it will be show time for