Re: Minimal logical decoding on standbys

tushar <tushar.ahuja@enterprisedb.com>

From: tushar <tushar.ahuja@enterprisedb.com>

To: Andres Freund <andres@anarazel.de>

Cc: Amit Khandekar <amitdkhan.pg@gmail.com>, Robert Haas <robertmhaas@gmail.com>, Petr Jelinek <petr.jelinek@2ndquadrant.com>, Craig Ringer <craig@2ndquadrant.com>, Petr Jelinek <petr@2ndquadrant.com>, pgsql-hackers <pgsql-hackers@postgresql.org>

Date: 2019-07-17T11:24:55Z

Lists: pgsql-hackers

Commits

Same data as JSON: GET /api/v1/messages/:b64id/commits the thread's linked commits as JSON, with link sources. API reference →

Reduce the log level in 035_standby_logical_decoding.pl.
- 3034dc56ef4b 16.0 landed
035_standby_logical_decoding: Add missing waits for replication
- 57411c82ce86 16.0 landed
For cascading replication, wake physical and logical walsenders separately
- e101dfac3a53 16.0 landed
Handle logical slot conflicts on standby
- 26669757b6a7 16.0 landed
Support invalidating replication slots due to horizon and wal_level
- be87200efd93 16.0 landed
Prevent use of invalidated logical slot in CreateDecodingContext()
- 4397abd0a2af 16.0 landed
Replace replication slot's invalidated_at LSN with an enum
- 15f8203a5975 16.0 landed
Pass down table relation into more index relation functions
- 61b313e47eb9 16.0 landed
Assert only valid flag bits are passed to visibilitymap_set()
- a88a18b1250b 16.0 landed
Remove unused _bt_delitems_delete() argument.
- dc43492e46c7 14.0 cited
Add xl_btree_delete optimization.
- d2e5e20e5711 13.0 cited

On 07/16/2019 10:56 PM, Andres Freund wrote:
> Even after calling pg_logical_slot_get_changes() multiple times? What
> does
> SELECT * FROM pg_replication_slots; before and after multiple calls return?
>
> Does manually forcing a checkpoint with CHECKPOINT; first on the primary
> and then the standby "fix" the issue?
>
Yes,eventually it gets clean up -after firing multiple times get_changes 
function or checkpoint or even both.
This same behavior we are able to see  on MASTER  -with or without patch.

but is this an old (existing) issue ?
>> b)pg_wal files are not recycling  and every time it is creating new files
>> after firing get_changes function
> I'm not sure what you mean by this. Are you saying that
> pg_logical_slot_get_changes() causes WAL to be written?

No, when i said - created new WAL files , i meant -after each pg_bench 
run NOT after executing  get_changes.

-- 
regards,tushar
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