# Tombstones warning, threshold, creating and removing tables every few hours, performance impacts

**URL:** <https://forum.scylladb.com/t/tombstones-warning-threshold-creating-and-removing-tables-every-few-hours-performance-impacts/4843>\
**Category:** ScyllaDB\
**Tags:** data-model, performance, tombstone, warning\
**Created:** [May 20, 2025, 7:13am UTC](https://forum.scylladb.com/t/tombstones-warning-threshold-creating-and-removing-tables-every-few-hours-performance-impacts/4843 "2025-05-20T07:13:46Z")\
**Posts on this page:** 1\
**Page:** 1

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**Author:** ![Guy](https://sea2.discourse-cdn.com/flex016/user_avatar/forum.scylladb.com/guy/32/9_2.png) [@Guy](https://forum.scylladb.com/u/Guy)\
**Post date:** [May 20, 2025, 7:13am UTC](https://forum.scylladb.com/t/tombstones-warning-threshold-creating-and-removing-tables-every-few-hours-performance-impacts/4843/1 "2025-05-20T07:13:46Z")

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> [@](#):
>
> [**Originally from the User Slack**](https://slack.scylladb.com/)
> 
> ![Nick_Vladiceanu](https://us1.discourse-cdn.com/flex016/uploads/scylladb/original/2X/0/059db617d110231ced9a984559a6da500b22c526.png) **@Nick\_Vladiceanu:** Hi folks,  
> we are seeing quite a lot of warnings regarding Tombstones in `system_schema` keyspace, Scylla 5.4.9:
> 
> ```auto
> WARN 2025-05-05 10:12:02,070 [shard 0:stat] querier - Read 210 live rows and 4109 tombstones for system_schema.tables <partition-range-scan> (-inf, +inf) (see tombstone_warn_threshold)
> WARN 2025-05-05 10:11:10,929 [shard 0:stat] querier - Read 288 live rows and 10003 tombstones for system_schema.columns <partition-range-scan> (-inf, +inf) (see tombstone_warn_threshold)
> 
> ```
> 
> As far as I understand, this can hurt the cluster performance. Can we do something to clean up those tombstones faster? Since the `gc_grace_seconds = 604800` and it’s immutable for this keyspace, what are the options? Thanks
> 
> ![Botond_Dénes](https://us1.discourse-cdn.com/flex016/uploads/scylladb/original/1X/873f80169aadc07303ca5e860a0fca5146ab38c6.jpeg) **@Botond\_Dénes:** Major compaction on the keyspace can help.  
> These tables are not read all the time, only on startup and on schema changes.
> 
> ![Nick_Vladiceanu](https://us1.discourse-cdn.com/flex016/uploads/scylladb/original/2X/0/059db617d110231ced9a984559a6da500b22c526.png) **@Nick\_Vladiceanu:** I have tried to execute a few times
> 
> ```auto
> nodetool compact system_schema
> 
> ```
> 
> Although it runs without issues, the warnings about tombstones are still present 🤔  
> We create and remove tables every 2-3 hours
> 
> ![Botond_Dénes](https://us1.discourse-cdn.com/flex016/uploads/scylladb/original/1X/873f80169aadc07303ca5e860a0fca5146ab38c6.jpeg) **@Botond\_Dénes:** In a recent version (don’t remember which exactly) we added a different method to purge tombstones, this would allow getting rid of most of them.  
> \> We create and remove tables every 2-3 hours  
> With this use-case you will have many tombstones, no way to avoid it.  
> The above mentioned improvement will help though.  
> You can look around in the release notes of later releases (6.0+) to see which one has this improvement. In any case I suggest upgrading, 5.4 is EOL for a while now.
> 
> ![Nick_Vladiceanu](https://us1.discourse-cdn.com/flex016/uploads/scylladb/original/2X/0/059db617d110231ced9a984559a6da500b22c526.png) **@Nick\_Vladiceanu:** Thanks a lot Botond. We have recently upgraded to 5.4 as preparation for the 6.x upgrade, which will follow soon. I will post here updates after the upgrade to 6.x.