Thanks for the insight, Rahul. We’re using 1 day for the time window.
compaction = {'class':
'com.jeffjirsa.cassandra.db.compaction.TimeWindowCompactionStrategy',
'compaction_window_size': '1',
'compaction_window_unit': 'DAYS',
'max_threshold': '32',
'min_threshold': '4',
'timestamp_resolution': 'MILLISECONDS',
'tombstone_compaction_interval': '86400',
'tombstone_threshold': '0.2',
'unchecked_tombstone_compaction': 'true'}'
AND
default_time_to_live = 7884009
AND
gc_grace_seconds = 86400
AND
read_repair_chance = 0
Whats the best way to examine the sstable data so that I can verify that it is
old data, other than by the min / max timestamps?
Thanks for your help
From: Rahul Singh [mailto:rahul.xavier.si...@gmail.com]
Sent: Tuesday, March 26, 2019 9:24 PM
To: user <user@cassandra.apache.org>
Subject: Re: TWCS Compactions & Tombstones
What's your timewindow? Roughly how much data is in each window?
If you examine the sstable data and see that is truly old data with little
chance that it has any new data, you can just remove the SStables. You can do a
rolling restart -- take down a node, remove mc-254400-* and then start it up.
rahul.xavier.si...@gmail.com<mailto:rahul.xavier.si...@gmail.com>
http://cassandra.link
On Tue, Mar 26, 2019 at 8:01 AM Nick Hatfield
<nick.hatfi...@metricly.com<mailto:nick.hatfi...@metricly.com>> wrote:
How does one properly rid of sstables that have fallen victim to overlapping
timestamps? I realized that we had TWCS set in our CF which also had a
read_repair = 0.1 and after correcting this to 0.0 I can clearly see the
affects over time on the new sstables. However, I still have old sstables that
date back some time last year, and I need to remove them:
Max: 09/05/2018 Min: 09/04/2018 Estimated droppable tombstones:
0.8832057909932046 13G Mar 26 11:34 mc-254400-big-Data.db
What is the best way to do this? This is on a production system so any help
would be greatly appreciated.
Thanks,
