Re: tombstones problem with 1.0.8

2012-04-04 Thread Ross Black
Hi Jonathan, Thanks for your response. We were running a compact at least once a day over the keyspace. The gc_grace was set to only 1 hour, so from what you said I would expect that tombstones should be deleted after max 3 days. When I inspected the data in the SSTables after a compact, some ro

Re: tombstones problem with 1.0.8

2012-04-03 Thread Jonathan Ellis
Removing expired columns actually requires two compaction passes: one to turn the expired column into a tombstone; one to remove the tombstone after gc_grace_seconds. (See https://issues.apache.org/jira/browse/CASSANDRA-1537.) Perhaps CASSANDRA-2786 was causing things to (erroneously) be cleaned u

Re: tombstones problem with 1.0.8

2012-03-28 Thread Ross Black
Hi Radim, I am hunting for what I believe is a bug in Cassandra and tombstone handling that may be triggered by our particular application usage. I appreciate your attempt to help, but without you actually knowing what our application is doing and why, your advice to change our application is poin

Re: tombstones problem with 1.0.8

2012-03-28 Thread Radim Kolar
Dne 28.3.2012 13:14, Ross Black napsal(a): Radim, We are only deleting columns. *Rows are never deleted.* i suggest to change app to delete rows. try composite keys.

Re: tombstones problem with 1.0.8

2012-03-28 Thread Ross Black
Radim, We are only deleting columns. *Rows are never deleted.* We are continually adding new columns that are then deleted. * Existing columns (deleted or otherwise) are never updated. * Ross* * On 28 March 2012 13:51, John Laban wrote: > (Radim: I'm assuming you mean "do not delete already d

Re: tombstones problem with 1.0.8

2012-03-27 Thread John Laban
(Radim: I'm assuming you mean "do not delete already deleted columns" as Ross doesn't delete his rows.) Just to be clear about Ross' situation: he continually inserts columns and later deletes columns from the same set of rows. As long as he *doesn't* *keep deleting already-deleted columns* (wh

Re: tombstones problem with 1.0.8

2012-03-27 Thread Radim Kolar
Dne 27.3.2012 11:13, Ross Black napsal(a): Any pointers on what I should be looking for in our application that would be stopping the deletion of tombstones? do not delete already deleted rows. On read cassandra returns deleted rows as empty in range slices.

Re: tombstones problem with 1.0.8

2012-03-27 Thread Ross Black
ely and > irrevocably delete this message and any copies.-Original Message- > From: Radim Kolar [mailto:h...@filez.com] > Sent: Sunday, March 25, 2012 13:20 > To: user@cassandra.apache.org > Subject: Re: tombstones problem with 1.0.8 > > Scenario 4 > T1 write column

RE: tombstones problem with 1.0.8

2012-03-25 Thread Viktor Jevdokimov
ately and irrevocably delete this message and any copies.-Original Message- From: Radim Kolar [mailto:h...@filez.com] Sent: Sunday, March 25, 2012 13:20 To: user@cassandra.apache.org Subject: Re: tombstones problem with 1.0.8 Scenario 4 T1 write column T2 Flush memtable to S1 T3 del row

Re: tombstones problem with 1.0.8

2012-03-25 Thread Radim Kolar
Scenario 4 T1 write column T2 Flush memtable to S1 T3 del row T4 flush memtable to S5 T5 tomstone S5 expires T6 S5 is compacted but not with S1 Result?

Re: tombstones problem with 1.0.8

2012-03-23 Thread Ross Black
r, please contact the sender immediately and > irrevocably delete this message and any copies. > > *From:* Ross Black [mailto:ross.w.bl...@gmail.com] > *Sent:* Friday, March 23, 2012 07:16 > *To:* user@cassandra.apache.org > *Subject:* Re: tombstones problem with 1.0.8 >

RE: tombstones problem with 1.0.8

2012-03-23 Thread Viktor Jevdokimov
message and any copies.-Original Message- From: Radim Kolar [mailto:h...@filez.com] Sent: Friday, March 23, 2012 13:28 To: user@cassandra.apache.org Subject: Re: tombstones problem with 1.0.8 Example: T1 < T2 < T3 at T1 write column at T2 delete row at T3 > tombstone expiration

Re: tombstones problem with 1.0.8

2012-03-23 Thread Radim Kolar
Example: T1 < T2 < T3 at T1 write column at T2 delete row at T3 > tombstone expiration do compact ( T1 + T2 ) and drop expired tombstone column from T1 will be alive again?

RE: tombstones problem with 1.0.8

2012-03-23 Thread Viktor Jevdokimov
> You are explaining that if i have expired row tombstone and there exists > later timestamp on this row that tombstone is not deleted? If this works that > way, it will be never deleted. Exactly. It is merged with new one. Example 1: a row with 1 column in sstable. delete a row, not a column.

Re: tombstones problem with 1.0.8

2012-03-23 Thread Radim Kolar
During compaction of selected sstables Cassandra checks the whole Column Family for the latest timestamp of the column/row, including other sstables and memtable. You are explaining that if i have expired row tombstone and there exists later timestamp on this row that tombstone is not deleted

RE: tombstones problem with 1.0.8

2012-03-23 Thread Viktor Jevdokimov
ror, please contact the sender immediately and irrevocably delete this message and any copies. From: Ross Black [mailto:ross.w.bl...@gmail.com] Sent: Friday, March 23, 2012 07:16 To: user@cassandra.apache.org Subject: Re: tombstones problem with 1.0.8 Hi Victor, Thanks for your response. Is t

Re: tombstones problem with 1.0.8

2012-03-22 Thread Ross Black
diately and > irrevocably delete this message and any copies. > > *From:* Ross Black [mailto:ross.w.bl...@gmail.com] > *Sent:* Thursday, March 22, 2012 03:38 > *To:* user@cassandra.apache.org > *Subject:* tombstones problem with 1.0.8 > > ** ** > > Hi, > > We recently

RE: tombstones problem with 1.0.8

2012-03-22 Thread Viktor Jevdokimov
March 22, 2012 03:38 To: user@cassandra.apache.org Subject: tombstones problem with 1.0.8 Hi, We recently moved from 0.8.2 to 1.0.8 and the behaviour seems to have changed so that tombstones are now not being deleted. Our application continually adds and removes columns from Cassandra. We

tombstones problem with 1.0.8

2012-03-21 Thread Ross Black
Hi, We recently moved from 0.8.2 to 1.0.8 and the behaviour seems to have changed so that tombstones are now not being deleted. Our application continually adds and removes columns from Cassandra. We have set a short gc_grace time (3600) since our application would automatically delete zombies i