Oke, thanks! So a column tombstone will only be removed if all row fragments are present in the tables being compacted.
I have a row called "Index" which contains columns like "page0", "page1", "page2", etc. Every several minutes, new columns are created and old ones deleted. The problem is that I now have an "Index" row in several SSTables, but the column tombstones are never deleted. And reading the "Index" row (and all its column tombstones) takes longer and longer. If I do a major compaction, all tombstones are deleted and reading the "index" row takes one millisecond again (and all the garbage-collect issues because of this). Is it not advised to use rows with many new column creates/deletes (because of how minor compactions work)? Thanks! Rene 2012/9/17 aaron morton <aa...@thelastpickle.com>: > Does minor compaction delete expired column-tombstones when the row is > also present in another table which is > > No. > Compaction is per Column Family. > > Tombstones will be expired by Minor Compaction if all fragments of the row > are contained in the SSTables being compacted. > > Cheers > > ----------------- > Aaron Morton > Freelance Developer > @aaronmorton > http://www.thelastpickle.com > > On 15/09/2012, at 6:32 AM, Rene Kochen <rene.koc...@schange.com> wrote: > > Hi all, > > Does minor compaction delete expired column-tombstones when the row is > also present in another table which is not subject to the minor > compaction? > > Example: > > Say there are 5 SStables: > > - Customers_0 (10 MB) > - Customers_1 (10 MB) > - Customers_2 (10 MB) > - Customers_3 (10 MB) > - Customers_4 (30 MB) > > A minor compaction is triggered which will compact the similar sized > tables 0 to 3. In these tables is a customer record with key "C1" with > an expired column tombstone. Customer "C1" is also present in table 4. > Will the minor compaction delete the column (i.e. will the tombstone > be present in the newly created table)? > > Thanks, > > Rene > >
