# WAL sequencerTxn \> writerTxn (and sometimes writerTxn \> sequencerTxn) Data lagging by 2 days in QuestDB 9.2.0

**URL:** <https://community.questdb.com/t/wal-sequencertxn-writertxn-and-sometimes-writertxn-sequencertxn-data-lagging-by-2-days-in-questdb-9-2-0/939>\
**Category:** Community\
**Tags:** question\
**Created:** [November 25, 2025, 1:43pm UTC](https://community.questdb.com/t/wal-sequencertxn-writertxn-and-sometimes-writertxn-sequencertxn-data-lagging-by-2-days-in-questdb-9-2-0/939 "2025-11-25T13:43:17Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![Surya\_H](https://yyz2.discourse-cdn.com/flex004/user_avatar/community.questdb.com/surya_h/32/496_2.png) [@Surya\_H](https://community.questdb.com/u/Surya_H)\
**Post date:** [November 25, 2025, 1:43pm UTC](https://community.questdb.com/t/wal-sequencertxn-writertxn-and-sometimes-writertxn-sequencertxn-data-lagging-by-2-days-in-questdb-9-2-0/939/1 "2025-11-25T13:43:17Z")

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Hi Team,  
We are facing an issue with WAL tables after importing data into QuestDB.  
**Issue Summary**

- We observe that **sequencerTxn is higher than writerTxn** in some WAL tables.

- At other times, we see the opposite: **writerTxn \> sequencerTxn**.

- When we re-run the same query after a few minutes, the mismatch sometimes disappears, but then appears again for other tables.

- **Writer counts are much lower than sequencer counts** in several tables, which seems to indicate the writer thread is lagging.

- Because of this, our **latest data is delayed by almost 2 days** , even though inserts are happening with current timestamps.

**Background**

- We imported large datasets from CSV into QuestDB.

- During import, we **disabled WAL** , and after the import finished we **re-enabled WAL** using `ALTER TABLE <name> SET WAL ON`.

- Could it be after enabling WAL, these transaction mismatches started appearing?

**Environment**

- **QuestDB Version:** 9.2.0

- **OS:** Ubuntu 22.04

- **Instance:** AWS EC2

- **CPU Load Average:** 5.37, 5.76, 5.94

**Problem We Are Trying to Solve**  
Our current data (latest timestamps) is falling behind by **~2 days** , and we suspect WAL replay or writer lag is the reason.  
We are unable to clearly understand:

1. **Why sequencerTxn and writerTxn become unaligned**

2. **Whether this is normal behavior or an indication of corruption/lag**

3. **Why writer is not catching up with sequencer**

4. **Whether disabling WAL → bulk import → enabling WAL can cause such issues**

5. **How we can fix the WAL lag and data delay**

**Request**  
Can someone help explain:

- What causes sequencerTxn and writerTxn mismatch?

- Is this expected under load, or does it indicate WAL replay issues?

- How to bring writer in sync and eliminate the 2-day lag?

- Any recommended checks or configuration tuning?

Please let me know if more logs or metrics are needed.  
Thank you!

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**Author:** ![nwoolmer](https://yyz2.discourse-cdn.com/flex004/user_avatar/community.questdb.com/nwoolmer/32/24_2.png) [@nwoolmer](https://community.questdb.com/u/nwoolmer)\
**Post date:** [November 25, 2025, 1:43pm UTC](https://community.questdb.com/t/wal-sequencertxn-writertxn-and-sometimes-writertxn-sequencertxn-data-lagging-by-2-days-in-questdb-9-2-0/939/2 "2025-11-25T13:43:28Z")

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Let’s pick it up on Slack.