Would this work:ALTER TABLE session_state WITH speculative_retry = '0ms';ALTER TABLE session_state WITH speculative_retry = '0PERCENTILE';I can't set it to 0, but was wondering if these would have the same effect?~EricOn Wed, Sep 9, 2015 at 8:19 AM, Eric Plowe <email@example.com> wrote:Interesting. I'll give it a try and report back my findings.Thank you, Michael.
On Wednesday, September 9, 2015, Laing, Michael <firstname.lastname@example.org> wrote:Perhaps a variation on https://issues.apache.org/jira/browse/CASSANDRA-9753?You could try setting speculative retry to 0 to avoid cross-dc reads.On Wed, Sep 9, 2015 at 7:55 AM, Eric Plowe <email@example.com> wrote:read_repair_chance: 0dclocal_read_repair_chance: 0.1
On Wednesday, September 9, 2015, Laing, Michael <firstname.lastname@example.org> wrote:What are your read repair settings?On Tue, Sep 8, 2015 at 9:28 PM, Eric Plowe <email@example.com> wrote:To further expand. We have two data centers, Miami and Dallas. Dallas is our disaster recovery data center. The cluster has 12 nodes, 6 in Miami and 6 in Dallas. The servers in Miami only read/write to Miami using data center aware load balancing policy of the driver. We have the problem when writing and reading to the Miami cluster with LOCAL_QUORUM.Regards,Eric
On Tuesday, September 8, 2015, Eric Plowe <firstname.lastname@example.org> wrote:Rob,All writes/reads are happening from DC1. DC2 is a backup. The web app does not handle live requests from DC2.Regards,Eric Plowe
On Tuesday, September 8, 2015, Robert Coli <email@example.com> wrote:On Tue, Sep 8, 2015 at 4:40 PM, Eric Plowe <firstname.lastname@example.org> wrote:I'm using Cassandra as a storage mechanism for session state persistence for an ASP.NET web application. I am seeing issues where the session state is persisted on one page (setting a value: Session["key"] = "value" and when it redirects to another (from a post back event) and check for the existence of the value that was set, it doesn't exist.It's a 12 node cluster with 2 data centers (6 and 6) running 2.1.9. The key space that the column family lives has a RF of 3 for each data center. The session state provider is using the the datastax csharp driver v2.1.6. Writes and reads are at LOCAL_QUORUM.1) Write to DC_A with LOCAL_QUORUM2) Replication to DC_B takes longer than it takes to...3) Read from DC_B with LOCAL_QUORUM, do not see the write from 1)If you want to be able to read your writes from DC_A in DC_B, you're going to need to use EACH_QUORUM.=Rob