Showing entries 61 to 70 of 154
« 10 Newer Entries | 10 Older Entries »
Displaying posts with tag: storage engine (reset)
MySQL on S3: security and backups

I got a few questions like the ones below that I’d like to address to avoid further confusion.
How exactly secure is ClouSE for MySQL, the first secure database in the cloud? Am I protected against standard application level security attacks or even accidental admin mistakes?
With the help of ClouSE I get instantaneous backup for my database on the highly durable cloud storage. But how would I protect my data in case a malicious attack or an accident did occur?

Re: security

I’ve got a comment pointing out that data encryption on the storage level doesn’t protect from SQL injections.  Of course, data encryption does not protect from SQL injections (as long as there is SQL involved, there will be a risk of a SQL injection).  Neither does it protect from the infinite number …

[Read more]
Dagstuhl Seminar on Database Workload Management

A few weeks ago Bradley Kuszmaul and I attended the Dagstuhl Seminar on Database Workload Management.

The Dagstuhl computer science research center is (remotely) located in the countryside in Saarland, Germany. The actual building is an 18th Century Manor House, first retooled as an old-age home, and then a computer science research center. Workshop participants typically spend the whole week talking and working together.

Dagstuhl Computer Science Center

Shivnath Babu (Duke University), Goetz Graefe (Hewlett Packard), and Harumi Kuno (Hewlett Packard) did a great job organizing. …

[Read more]
Real World Compression

Benchmarking is a tricky thing, especially when it comes to compression. Some data compresses quite well while other data does not compress at all. Storing jpeg images in a BLOB column produces 0% compression, but storing the string “AAAAAAAAAAAAAAAAAAAA” in a VARCHAR(20) column produces extremely high (and unrealistic) compression numbers.

This week I was assisting a TokuDB customer understand the insertion performance of TokuDB versus InnoDB and MyISAM for their actual data. The table contained a single VARCHAR(50), multiple INTEGER, one SET, one DECIMAL, and a surrogate primary key.  To support a varied query workload they needed 6 indexes.

Here is an obfuscated schema of the table:

col1 varchar(50) NOT NULL,
col2 int(40) NOT NULL DEFAULT '0',
col3 int(10) NOT NULL DEFAULT '0',
col4 int(10) NOT NULL DEFAULT '0',
col5 int(10) NOT NULL DEFAULT '0',
col6 set('val1', 'val2', ..., ‘val19’, 'val20',) NOT NULL DEFAULT …
[Read more]
Webinar: Understanding Indexing

Three rules on making indexes around queries to provide good performance

Application performance often depends on how fast a query can respond and query performance almost always depends on good indexing. So one of the quickest and least expensive ways to increase application performance is to optimize the indexes. This talk presents three simple and effective rules on how to construct indexes around queries that result in good performance.


Time: 2PM EDT / 11AM PDT

This webinar is a general discussion applicable to all databases using indexes and is not specific to any particular MySQL® storage engine (e.g., InnoDB, TokuDB®, etc.). The rules are explained using a simple model that does NOT rely on understanding B-trees, Fractal Tree® indexing, …

[Read more]
How We Spent a Tuesday Fixing a MySQL Replication Bug

We found a simple XA transaction that crashes MySQL 5.5 replication. This simple transaction inserts a row into an InnoDB table and a TokuDB table. The bug was caused by a flaw in the logging code exposed by the transaction’s use of two XA storage engines (TokuDB and InnoDB). This bug was fixed in the TokuDB 6.0.1 release.

Here are some details.  Suppose that a database contains the following tables.

create table t1 (a int) engine=InnoDB
create table t2 (a int) engine=TokuDB

 The following transaction

begin
insert into t1 values (1)
insert into t2 values (2)
commit

causes the replication slave to crash.

The crash occurs when mysqld tries to dereference a NULL pointer.

#4  0x000000000088e203 in MYSQL_BIN_LOG::log_and_order (this=0x14b8640, thd=0x7f7758000af0, xid=161, all=true, need_prepare_ordered=false, need_commit_ordered=true) at …

[Read more]
My Talks at MySQL Connect and Percona Live NYC


Solving the Challenges of Big Databases with MySQL

When you’re using MySQL for big data (more than ten times as large as main memory), these challenges often arise: loading data fast; maintaining indexes under insertions deletions, and updates; adding and removing columns online; adding indexes online; preventing slave lag; and compressing data effectively.

This session shows why some of these challenges are difficult to solve with storage engines based on B-trees, how Fractal Tree® data structures work, and why they can help solve these problems. Tokutek sells a transaction-safe Fractal Tree storage engine for MySQL, but the presentation is primarily about the underlying technology. It includes a discussion of both the theoretical and practical aspects of Fractal Tree indexes.

I have the privilege of being able to give this talk at both conferences, so please stop by my presentation at …

[Read more]
How to Stop Playing “Hop and Seek”: MySQL Cluster and TokuDB, Part 2

In my last post, I wrote that I observed many similarities between TokuDB and MySQL Cluster. Many features that benefit TokuDB also benefit MySQL Cluster, and vice versa, with Hot Column Addition and Deletion (HCAD) being an example. Over my next few posts, I expand on some more of these possibly unexpected similarities.

Today I want to focus on optimizer support for clustering keys. Both MySQL Cluster and TokuDB can benefit from the MySQL optimizer supporting clustering keys. For TokuDB, the benefit is obvious, as TokuDB supports clustering keys. A non-negligible part of our effort is changing the …

[Read more]
Hot Table Optimization with MySQL

Table optimization is a necessary evil; tables sometimes need to be optimized to reclaim space or to improve query performance.  Unfortunately, MySQL blocks writes to a table while it is being optimized.  Because optimization time is proportional to the table size, writes can be blocked for a long time.  Fractal Tree indexes support online optimization; however, the MySQL metadata lock gets in the way of writing while optimizing.  We will describe a simple patch to MySQL that enables online optimization of TokuDB tables.

Why do tables need to be optimized?  Here are some reasons.

  • Insertions with random keys can result in a tree with underutilized leaf blocks.  Many tree algorithms split nodes in half when they become full.  If these nodes are stored in fixed sized blocks, like many B-trees do, then there can be a lot of wasted space.  Table optimization of B-trees write blocks with less …
[Read more]
Volver – MySQL, NoSQL, and Cloud Conference Latin America

Volver,
con la frente marchita,
las nieves del tiempo
platearon mi sien…

Martin’s blog (Mi Buenos Aires Querido) was named after a tango, so I decided to follow his lead. The 4 lines of the refrain make reference to someone returning to Buenos Aires after 20 years, now looking a little bit older. I moved to the US about 15 years ago and have returned many times to visit. However, I have never gone back to participate in an event like this with so many renowned speakers from the MySQL community. The list include many people with whom I have worked with over the past decade. …

[Read more]
How to Stop Playing “Hop and Seek”: MySQL Cluster and TokuDB

As a TokuDB storage engine developer, numerous times I’ve been struck by the similarities between MySQL Cluster and TokuDB. Namely, many times where I find myself thinking, “TokuDB would benefit from this feature”, I also end up thinking “MySQL Cluster would benefit from this feature” as well.

At first glance, one may wonder why. TokuDB is a storage engine designed to work well on big data, providing compression, agility, and performance, while MySQL Cluster is a distributed database solution (http://www.mysql.com/products/cluster/) that provides (among many other things) auto sharding and 99.999% availability. TokuDB’s innovation, Fractal Trees® indexes, are designed to drastically reduce the number of disk seeks performed, but TokuDB still operates on a hard disk. MySQL Cluster operates over a network. How can we be two peas in a pod?

But when I …

[Read more]
Showing entries 61 to 70 of 154
« 10 Newer Entries | 10 Older Entries »