Cassandra-11206 (https://issues.apache.org/jira/browse/CASSANDRA-11206) is in 3.11 and does have a few knobs to make this less painful
You can also increase the column index size from 64kb to something significantly higher to decrease the cost of those reads on the JVM (shifting cost to the disk) - consider 256k or 512k for 100-1000mb partitions. -- Jeff Jirsa > On Feb 13, 2019, at 5:48 AM, Durity, Sean R <sean_r_dur...@homedepot.com> > wrote: > > Agreed. It’s pretty close to impossible to administrate your way out of a > data model that doesn’t play to Cassandra’s strengths. Which is true for > other data storage technologies – you need to model the data the way that the > engine is designed to work. > > > Sean Durity > > From: DuyHai Doan <doanduy...@gmail.com> > Sent: Wednesday, February 13, 2019 8:08 AM > To: user <user@cassandra.apache.org> > Subject: [EXTERNAL] Re: Make large partitons lighter on select without > changing primary partition formation. > > Plain answer is NO > > There is a slight hope that the JIRA > https://issues.apache.org/jira/browse/CASSANDRA-9754 gets into 4.0 release > > But right now, there seems to be few interest in this ticket, the last > comment 23/Feb/2017 old ... > > > On Wed, Feb 13, 2019 at 1:18 PM Vsevolod Filaretov <vsfilare...@gmail.com> > wrote: > Hi all, > > The question. > > We have Cassandra 3.11.1 with really heavy primary partitions: > cfhistograms 95%% is 130+ mb, 95%% cell count is 3.3mln and higher, 98%% > partition size is 220+ mb sometimes partitions are 1+ gb. We have regular > problems with node lockdowns leading to read request timeouts under read > requests load. > > Changing primary partition key structure is out of question. > > Are there any sharding techniques available to dilute partitions at level > lower than 'select' requests to make read performance better? Without > changing read requests syntax? > > Thank you all in advance, > Vsevolod Filaretov. > > > The information in this Internet Email is confidential and may be legally > privileged. It is intended solely for the addressee. Access to this Email by > anyone else is unauthorized. If you are not the intended recipient, any > disclosure, copying, distribution or any action taken or omitted to be taken > in reliance on it, is prohibited and may be unlawful. When addressed to our > clients any opinions or advice contained in this Email are subject to the > terms and conditions expressed in any applicable governing The Home Depot > terms of business or client engagement letter. The Home Depot disclaims all > responsibility and liability for the accuracy and content of this attachment > and for any damages or losses arising from any inaccuracies, errors, viruses, > e.g., worms, trojan horses, etc., or other items of a destructive nature, > which may be contained in this attachment and shall not be liable for direct, > indirect, consequential or special damages in connection with this e-mail > message or its attachment.
