Hi Adrian, Thank you for your response. Please find the requested details below:
*PostgreSQL Version:* Source: PostgreSQL 11.15 Target: PostgreSQL 16.9 *Operating System:* Source: RHEL 7.9 Target: RHEL 9.6 *Network Distance:* Both servers are in the same data center, connected through a high-speed internal network (low latency). Logical Replication Settings: *Source - Postgres 11.15.* -- ==== WAL & Replication Settings ==== wal_level = 'logical' max_wal_senders = '30' max_replication_slots = '20' wal_keep_segments = '800' wal_sender_timeout = '300s' max_worker_processes = '32' max_logical_replication_workers = '16' max_sync_workers_per_subscription = '8' ==== WAL & Checkpoint ==== max_wal_size = '40GB' min_wal_size = '4GB' checkpoint_timeout = '45min' checkpoint_completion_target = '0.9' ==== Memory ==== shared_buffers = '18GB' work_mem = '128MB' maintenance_work_mem = 4GB' effective_cache_size = '275GB' *Target DB Postgres 16.10* ==== Logical Replication Settings ==== max_worker_processes = '32' max_logical_replication_workers = '16' max_sync_workers_per_subscription = '8' wal_receiver_timeout = '300s' ==== WAL & Checkpoint ==== checkpoint_timeout = '45min' checkpoint_completion_target = '0.9' max_wal_size = '40GB' min_wal_size = '4GB' ==== Memory ==== shared_buffers = '18GB' work_mem = '128MB' maintenance_work_mem = '4GB' effective_cache_size = '275GB' synchronous_commit = 'off' Since you have already started is that not already to late for this? Yes We are currently in the *testing phase* and validating with the above parameters. However, the replication process has been *extremely slow — it’s been running for the past 5 days* with limited progress. Any specific tuning recommendations or best practices to improve performance at this stage would be greatly appreciated. Thanks & Regards Krishna. On Wed, 5 Nov 2025 at 21:07, Adrian Klaver <[email protected]> wrote: > On 11/4/25 22:27, Bala M wrote: > > Thank you all for your suggestions, > > > > Thanks for your quick response and for sharing the details. > > After reviewing the options, the logical replication approach seems to > > be the most feasible one with minimal downtime. > > > > However, we currently have 7 streaming replication setups running from > > production, with a total database size of around 15 TB. Out of this, > > there are about 10 large tables ranging from 1 TB (max) to 50 GB (min) > > each, along with approximately 150+ sequences. > > > > Could you please confirm if there are any successful case studies or > > benchmarks available for a similar setup? > > Since you have given minimal information in this post, I doubt there is > really a way to compare to other situations. Collect the details you > provided earlier in the thread for those folks getting to it just now. > > That would be: > > 1) Postgres versions on both ends > > 2) OS and versions on both ends. > > 3) Network distance between 'machines'. > > 4) The logical replication settings. > > > Additionally, please share any recommended parameter tuning or best > > practices for handling logical replication at this scale. > > Since you have already started is that not already to late for this? > > > > > > > Current server configuration: > > > > CPU: 144 cores > > > > RAM: 512 GB > > > > > > Thanks & Regards > > Krishna. > > > > > > -- > Adrian Klaver > [email protected] >
