Why does not the default snapshot strategy remove the old and useless dump file?

[XiaooLei]

I am trying to use dragonfly in our systems, but when I was configuring it, I found the the default strategy just don't remove the old snapshot files even if new snapshot file is generated, and as time goes, the snapshot files grows so big and takes up so much storage space. this is different than the Redis snapshot strategy. I finally managed to make it align to Redis by adding command args '''--dbfilename dump.rdb --nodf_snapshot_format''' , But I still can not figure out why dragonfly team use such a seeming useless snapshot strategy? Really appreciated if my question could be answered

[romange]

@XiaooLei why did you specify --nodf_snapshot_format?

[liusf1993]

I didn't find any doc abount flag nodf_snapshot_format, and only found flag df_snapshot_format,

df_snapshot_format - Set true to save dump in Dragonfly file format (true by default).

Is it be the same with df_snapshot_format=false ?
It seems that while df_snapshot_format=true , snapshot dump file name has timestamps, so many snapshots may kept.
While `df_snapshot_format=false', it is the same with redis snapshot strategy.Is my conjecture correct?

[liusf1993]

Oh,I misunderstood, I saw the explaination in the linkhttps://github.com/dragonflydb/dragonfly/issues/1377