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Search Results for: xa transactions

On TokuMX (and MongoDB) Replication and Transactions

In my last post, I describe the differences between a TokuMX oplog entry and a MongoDB oplog entry. One reason why the entries are so different is that TokuMX supports multi-statement and multi-document transactions. In …


Lock Escalation and Big Transactions in TokuDB and TokuMX

We have seen TokuDB lock escalation stall the execution of SQL operations for tens of seconds. To address this problem, we changed the lock escalation algorithm used by TokuDB and TokuMX so that the cost …


February 6 Webinar: Transactions and MongoDB – Ways To Have It All

MongoDB is loved by developers for its productivity, but productivity can decline when you begin to write enterprise applications and realize that some database features you take for granted are not available in MongoDB. One …


Four Benefits of TokuMX Transactions for MongoDB Applications

From the application’s perspective, TokuMX behaves very similarly, if not identically, to MongoDB in many ways. But in one subtle yet important way, on non-sharded clusters, TokuMX is different. With MongoDB, operations on each single …


Introducing TokuMX Transactions for MongoDB Applications

Since our initial release last summer, TokuMX has supported fully ACID and MVCC multi-statement transactions. I’d like to take this post to explain exactly what we’ve done and what features are now available to the …


A TokuDB Stall Caused by Conflicting Transactions When Opening a Table

One of our customers reported that ‘create table select from’ statements stall for a period of time equal to the TokuDB lock timeout.  This indicated a lock conflict between multiple transactions.  In addition, other MySQL …


Repair MySQL 5.6 GTID replication by injecting empty transactions

In a previous post I explained how to repair MySQL 5.6 GTID replication using two different methods. I didn’t mention the famous SET GLOBAL SQL_SLAVE_SKIP_COUNTER = n for a simple reason, it doesn’t work anymore …


How to debug long-running transactions in MySQL

Among the many things that can cause a “server stall” is a long-running transaction. If a transaction remains open for a very long time without committing, and has modified data, then other transactions could block …


What is innodb_support_xa?

A common misunderstanding about innodb_support_xa is that it enables user-initiated XA transactions, that is, transactions that are prepared and then committed on multiple systems, with an external transaction coordinator. This is actually not precisely what …


High Insertion Rates into a TokuDB Table with Durable Transactions

We recently made transactions in TokuDB 3.0 durable. We write table changes into a log file so that in the event of a crash, the table changes up to the last checkpoint can be replayed. …