Thanks Duo. --- Mallikarjun
On Sun, Jul 25, 2021 at 7:32 PM 张铎(Duo Zhang) <palomino...@gmail.com> wrote: > Replied on jira. Please give more details about what you are doing in the > PR... > > Thanks. > > Mallikarjun <mallik.v.ar...@gmail.com> 于2021年7月25日周日 上午10:48写道： > > > > Can someone review this pull request? > > https://github.com/apache/hbase/pull/3359 > > > > This change changes meta information for backup, if not part of hbase > > 3.0.0. It might have a lot of additional work to be put into executing > the > > above mentioned plan. > > > > --- > > Mallikarjun > > > > > > On Thu, Feb 11, 2021 at 5:36 PM Mallikarjun <mallik.v.ar...@gmail.com> > > wrote: > > > > > Slight modification to previous version --> https://ibb.co/Nttx3J1 > > > > > > --- > > > Mallikarjun > > > > > > > > > On Thu, Feb 11, 2021 at 8:12 AM Mallikarjun <mallik.v.ar...@gmail.com> > > > wrote: > > > > > >> Inline Reply > > >> > > >> On Wed, Feb 3, 2021 at 6:44 AM Sean Busbey <bus...@apache.org> wrote: > > >> > > >>> Hi Mallikarjun, > > >>> > > >>> Those goals sound worthwhile. > > >>> > > >>> Do you have a flow chart similar to the one you posted for the > current > > >>> system but for the proposed solution? > > >>> > > >> > > >> This is what I am thinking --> https://ibb.co/KmH6Cwv > > >> > > >> > > >>> > > >>> How much will we need to change our existing test coverage to > accommodate > > >>> the proposed solution? > > >>> > > >> > > >> Of the 38 tests, it looks like we might have to change a couple only. > > >> Will have to add more tests to cover parallel backup scenarios. > > >> > > >> > > >>> > > >>> How much will we need to update the existing reference guide section? > > >>> > > >>> > > >> Probably nothing. Interface as such will not change. > > >> > > >> > > >>> > > >>> On Sun, Jan 31, 2021, 04:59 Mallikarjun <mallik.v.ar...@gmail.com> > > >>> wrote: > > >>> > > >>> > Bringing up this thread. > > >>> > > > >>> > On Mon, Jan 25, 2021, 3:38 PM Viraj Jasani <vjas...@apache.org> > wrote: > > >>> > > > >>> > > Thanks, the image is visible now. > > >>> > > > > >>> > > > Since I wanted to open this for discussion, did not consider > > >>> placing it > > >>> > > in > > >>> > > *hbase/dev_support/design-docs*. > > >>> > > > > >>> > > Definitely, only after we come to concrete conclusion with the > > >>> reviewer, > > >>> > we > > >>> > > should open up a PR. Until then this thread is anyways up for > > >>> discussion. > > >>> > > > > >>> > > > > >>> > > On Mon, 25 Jan 2021 at 1:58 PM, Mallikarjun < > > >>> mallik.v.ar...@gmail.com> > > >>> > > wrote: > > >>> > > > > >>> > > > Hope this link works --> https://ibb.co/hYjRpgP > > >>> > > > > > >>> > > > Inline reply > > >>> > > > On Mon, Jan 25, 2021 at 1:16 PM Viraj Jasani < > vjas...@apache.org> > > >>> > wrote: > > >>> > > > > > >>> > > > > Hi, > > >>> > > > > > > >>> > > > > Still not available :) > > >>> > > > > The attachments don’t work on mailing lists. You can try > > >>> uploading > > >>> > the > > >>> > > > > attachment on some public hosting site and provide the url > to the > > >>> > same > > >>> > > > > here. > > >>> > > > > > > >>> > > > > Since I am not aware of the contents, I cannot confirm right > > >>> away but > > >>> > > if > > >>> > > > > the reviewer feels we should have the attachment on our > github > > >>> repo: > > >>> > > > > hbase/dev-support/design-docs , good to upload the content > there > > >>> > later. > > >>> > > > For > > >>> > > > > instance, pdf file can contain existing design and new design > > >>> > diagrams > > >>> > > > and > > >>> > > > > talk about pros and cons etc once we have things finalized. > > >>> > > > > > > >>> > > > > > > >>> > > > Since I wanted to open this for discussion, did not consider > > >>> placing it > > >>> > > in > > >>> > > > *hbase/dev_support/design-docs*. > > >>> > > > > > >>> > > > > > >>> > > > > > > >>> > > > > On Mon, 25 Jan 2021 at 12:13 PM, Mallikarjun < > > >>> > mallik.v.ar...@gmail.com > > >>> > > > > > >>> > > > > wrote: > > >>> > > > > > > >>> > > > > > Attached as image. Please let me know if it is availabe > now. > > >>> > > > > > > > >>> > > > > > --- > > >>> > > > > > Mallikarjun > > >>> > > > > > > > >>> > > > > > > > >>> > > > > > On Mon, Jan 25, 2021 at 10:32 AM Sean Busbey < > > >>> bus...@apache.org> > > >>> > > > wrote: > > >>> > > > > > > > >>> > > > > >> Hi! > > >>> > > > > >> > > >>> > > > > >> Thanks for the write up. unfortunately, your image for the > > >>> > existing > > >>> > > > > >> design didn't come through. Could you post it to some > host and > > >>> > link > > >>> > > it > > >>> > > > > >> here? > > >>> > > > > >> > > >>> > > > > >> On Sun, Jan 24, 2021 at 3:12 AM Mallikarjun < > > >>> > > mallik.v.ar...@gmail.com > > >>> > > > > > > >>> > > > > >> wrote: > > >>> > > > > >> > > > >>> > > > > >> > Existing Design: > > >>> > > > > >> > > > >>> > > > > >> > > > >>> > > > > >> > > > >>> > > > > >> > Problem 1: > > >>> > > > > >> > > > >>> > > > > >> > With this design, Incremental and Full backup can't be > run > > >>> in > > >>> > > > parallel > > >>> > > > > >> and leading to degraded RPO's in case Full backup is of > longer > > >>> > > > duration > > >>> > > > > esp > > >>> > > > > >> for large tables. > > >>> > > > > >> > > > >>> > > > > >> > Example: > > >>> > > > > >> > Expectation: Say you have a big table with 10 TB and > your > > >>> RPO is > > >>> > > 60 > > >>> > > > > >> minutes and you are allowed to ship the remote backup > with 800 > > >>> > Mbps. > > >>> > > > And > > >>> > > > > >> you are allowed to take Full Backups once in a week and > rest > > >>> of > > >>> > them > > >>> > > > > should > > >>> > > > > >> be incremental backups > > >>> > > > > >> > > > >>> > > > > >> > Shortcoming: With the above design, one can't run > parallel > > >>> > backups > > >>> > > > and > > >>> > > > > >> whenever there is a full backup running (which takes > roughly > > >>> 25 > > >>> > > hours) > > >>> > > > > you > > >>> > > > > >> are not allowed to take incremental backups and that > would be > > >>> a > > >>> > > breach > > >>> > > > > in > > >>> > > > > >> your RPO. > > >>> > > > > >> > > > >>> > > > > >> > Proposed Solution: Barring some critical sections such > as > > >>> > > modifying > > >>> > > > > >> state of the backup on meta tables, others can happen > > >>> parallelly. > > >>> > > > > Leaving > > >>> > > > > >> incremental backups to be able to run based on older > > >>> successful > > >>> > > full / > > >>> > > > > >> incremental backups and completion time of backup should > be > > >>> used > > >>> > > > > instead of > > >>> > > > > >> start time of backup for ordering. I have not worked on > the > > >>> full > > >>> > > > > redesign, > > >>> > > > > >> and will be doing so if this proposal seems acceptable > for the > > >>> > > > > community. > > >>> > > > > >> > > > >>> > > > > >> > Problem 2: > > >>> > > > > >> > > > >>> > > > > >> > With one backup at a time, it fails easily for a > > >>> multi-tenant > > >>> > > > system. > > >>> > > > > >> This poses following problems > > >>> > > > > >> > > > >>> > > > > >> > Admins will not be able to achieve required RPO's for > their > > >>> > tables > > >>> > > > > >> because of dependence on other tenants present in the > system. > > >>> As > > >>> > one > > >>> > > > > tenant > > >>> > > > > >> doesn't have control over other tenants' table sizes and > > >>> hence the > > >>> > > > > duration > > >>> > > > > >> of the backup > > >>> > > > > >> > Management overhead of setting up a right sequence to > > >>> achieve > > >>> > > > required > > >>> > > > > >> RPO's for different tenants could be very hard. > > >>> > > > > >> > > > >>> > > > > >> > Proposed Solution: Same as previous proposal > > >>> > > > > >> > > > >>> > > > > >> > Problem 3: > > >>> > > > > >> > > > >>> > > > > >> > Incremental backup works on WAL's and > > >>> > > > > >> org.apache.hadoop.hbase.backup.master.BackupLogCleaner > ensures > > >>> > that > > >>> > > > > WAL's > > >>> > > > > >> are never cleaned up until the next backup (Full / > > >>> Incremental) is > > >>> > > > > taken. > > >>> > > > > >> This poses following problem > > >>> > > > > >> > > > >>> > > > > >> > WAL's can grow unbounded in case there are transient > > >>> problems > > >>> > like > > >>> > > > > >> backup site facing issues or anything else until next > backup > > >>> > > scheduled > > >>> > > > > goes > > >>> > > > > >> successful > > >>> > > > > >> > > > >>> > > > > >> > Proposed Solution: I can't think of anything better, > but I > > >>> see > > >>> > > this > > >>> > > > > can > > >>> > > > > >> be a potential problem. Also, one can force full backup if > > >>> > required > > >>> > > > WAL > > >>> > > > > >> files are missing for whatever other reasons not > necessarily > > >>> > > mentioned > > >>> > > > > >> above. > > >>> > > > > >> > > > >>> > > > > >> > --- > > >>> > > > > >> > Mallikarjun > > >>> > > > > >> > > >>> > > > > > > > >>> > > > > > > >>> > > > > > >>> > > > > >>> > > > >>> > > >> >
