DBMS product categories
Analysis of database management technology in specific product categories. Related subjects include:
Daniel Abadi on Kickfire and related subjects
Daniel Abadi has a new blog, whose first post centers around Kickfire. The money quote is (emphasis mine):
In order for me to get excited about Kickfire, I have to ignore Mike Stonebraker’s voice in my head telling me that DBMS hardware companies have been launched many times in the past are ALWAYS fail (the main reasoning is that Moore’s law allows for commodity hardware to catch up in performance, eventually making the proprietary hardware overpriced and irrelevant). But given that Moore’s law is transforming into increased parallelism rather than increased raw speed, maybe hardware DBMS companies can succeed now where they have failed in the past
Good point.
More generally, Abadi speculates about the market for MySQL-compatible data warehousing. My responses include:
- OF COURSE there are many MySQL users who need to move to a serious analytic DBMS.
- What’s less clear is whether there’s any big advantage to those users in remaining MySQL-compatible when they do move. I’m not sure what MySQL-specific syntax or optimizations they’d have that would be difficult to port to a non-MySQL system.
- It’s nice to see Abadi speaking well of Infobright and its technology.
- To say that Infobright went open source because it was “desperate” is overstated. That said, I don’t think Infobright was on track to prosper without going open source.
- While open source and MySQL go together, an appliance like Kickfire loses many (not all) of the benefits of open source.
- Calpont has indeed never disclosed a customer win. Any year now … (Just kidding, Vogel!)
- In general, seeing Abadi be so favorable toward Vertica competitors adds credibiity to the recent Hadoop vs. DBMS paper.
Anyhow, as previously noted, I’m a big Daniel Abadi fan. I look forward to seeing what else he posts in his blog, and am optimistic he’ll live up to or exceed its stated goals.
| Categories: Calpont, Columnar database management, Data warehouse appliances, Data warehousing, DBMS product categories, Infobright, Kickfire, MySQL, Open source, Theory and architecture | 2 Comments |
Yet more on MySQL forks and storage engines
The issue of MySQL forks and their possible effect on closed-source storage engine vendors continues to get attention. The underlying question is:
Suppose Oracle wants to make life difficult for third-party storage engine vendors via its incipient control of MySQL? Can the storage engine vendors insulate themselves from this risk by working with a MySQL fork?
| Categories: MySQL, Open source, PostgreSQL | 11 Comments |
MySQL forking heats up, but not yet to the benefit of non-GPLed storage engine vendors
Last month, I wrote “This is a REALLY good time to actively strengthen the MySQL forkers,” largely on behalf of closed-source/dual-source MySQL storage engine vendors such as Infobright, Kickfire, Calpont, Tokutek, or ScaleDB. Yesterday, two of my three candidates to lead the effort — namely Monty Widenius/MariaDB/Monty Program AB and Percona — came together to form something called the Open Database Alliance. Details may be found:
- On the Open Database Alliance website
- In a press release
- On Monty Widenius’ blog
- In a Stephen O’Grady blog post based on a discussion with Monty Widenius
- In an ars technica blog post based on a discussion with Monty Program AB’s Kurt von Finck
But there’s no joy for the non-GPLed MySQL storage engine vendors in the early news. Read more
| Categories: MySQL, Open source, Theory and architecture | 16 Comments |
The secret sauce to Clearpace’s compression
In an introduction to archiving vendor Clearpace last December, I noted that Clearpace claimed huge compression successes for its NParchive product (Clearpace likes to use a figure of 40X), but didn’t give much reason that NParchive could compress a lot more effectively than other columnar DBMS. Let me now follow up on that.
To the extent there’s a Clearpace secret sauce, it seems to lie in NParchive’s unusual data access method. NParchive doesn’t just tokenize the values in individual columns; it tokenizes multi-column fragments of rows. Which particular columns to group together in that way seems to be decided automagically; the obvious guess is that this is based on estimates of the cardinality of their Cartesian products.
Of the top of my head, examples for which this strategy might be particularly successful include:
- Denormalized databases
- Message stores with lots of header information
- Addresses
| Categories: Archiving and information preservation, Columnar database management, Database compression, Rainstor | 8 Comments |
Oracle’s hardware strategy
Larry Ellison stated clearly in an email interview with Reuters (links here and here) that Oracle intends to keep Sun’s hardware business and indeed intends to invest in the SPARC chip. Naturally, I have a few thoughts about this.
As Stephen O’Grady points out, Sun’s main strength lay in selling to the large enterprise market. Well, that’s Oracle’s overwhelming focus too. As I noted two years ago:
One Oracle response is to provide lots of add-on technologies for high-end customers, on the database and middle tiers alike. In app servers it’s done surprisingly well against BEA. It’s sold a lot of clustering. And it’s bought into and tried to popularize niche technologies like TimesTen and Tangosol’s.
This all makes perfect sense – it’s a great fit for Oracle’s best customers, and a way to get thousands of extra dollars per server from enterprises that may already have bought all-you-can-eat licenses to the Oracle DBMS. And being so sensible, it fits into the Clayton Christensen disruption story in two ways:
Oracle may be helpless against mid-tier competition, but it sure has the high-end core of its market locked up.
- As one type of technology is commoditized, value is created in other parts of the technology stack.
Oracle’s ongoing acquisition spree in system software, application software, and now hardware just supports that story. MySQL, embedded Java, and so on may be welcome to Oracle as yet more opportunities to tap additional markets — but Oracle’s emphasis is and surely will remain on the large enterprise market.
The next notable point may be found in Larry’s key quote: Read more
| Categories: Data warehouse appliances, Data warehousing, Exadata, HP and Neoview, IBM and DB2, Oracle | 8 Comments |
eBay’s two enormous data warehouses
A few weeks ago, I had the chance to visit eBay, meet briefly with Oliver Ratzesberger and his team, and then catch up later with Oliver for dinner. I’ve already alluded to those discussions in a couple of posts, specifically on MapReduce (which eBay doesn’t like) and the astonishingly great difference between high- and low-end disk drives (to which eBay clued me in). Now I’m finally getting around to writing about the core of what we discussed, which is two of the very largest data warehouses in the world.
Metrics on eBay’s main Teradata data warehouse include:
- >2 petabytes of user data
- 10s of 1000s of users
- Millions of queries per day
- 72 nodes
- >140 GB/sec of I/O, or 2 GB/node/sec, or maybe that’s a peak when the workload is scan-heavy
- 100s of production databases being fed in
Metrics on eBay’s Greenplum data warehouse (or, if you like, data mart) include:
- 6 1/2 petabytes of user data
- 17 trillion records
- 150 billion new records/day, which seems to suggest an ingest rate well over 50 terabytes/day
- 96 nodes
- 200 MB/node/sec of I/O (that’s the order of magnitude difference that triggered my post on disk drives)
- 4.5 petabytes of storage
- 70% compression
- A small number of concurrent users
| Categories: Analytic technologies, Data warehouse appliances, Data warehousing, eBay, Greenplum, Petabyte-scale data management, Teradata, Web analytics | 48 Comments |
Data warehouse storage options — cheap, expensive, or solid-state disk drives
This is a long post, so I’m going to recap the highlights up front. In the opinion of somebody I have high regard for, namely Carson Schmidt of Teradata:
- There’s currently a huge — one order of magnitude — performance difference between cheap and expensive disks for data warehousing workloads.
- New disk generations coming soon will have best-of-both-worlds aspects, combining high-end performance with lower-end cost and power consumption.
- Solid-state drives will likely add one or two orders of magnitude to performance a few years down the road. Echoing the most famous logjam in VC history — namely the 60+ hard disk companies that got venture funding in the 1980s — 20+ companies are vying to cash in.
In other news, Carson likes 10 Gigabit Ethernet, dislikes Infiniband, and is “ecstatic” about Intel’s Nehalem, which will be the basis for Teradata’s next generation of servers.
| Categories: Data warehouse appliances, Data warehousing, eBay, Solid-state memory, Storage, Teradata | 16 Comments |
Some DB2 highlights
I chatted with IBM Thursday, about recent and imminent releases of DB2 (9.5 through 9.7). Highlights included:
- DB2 is getting Oracle emulation, which I posted about separately.
- IBM says that it had >50 new DB2 data warehouse customers last year. I neglected to ask how many of these had been general-purpose DB2 customers all along.
- By “data warehouse customer” I mean a user for InfoSphere Warehouse, which previously was called DB2’s DPF (Data Partitioning Feature). Apparently, this includes both logical and physical partitioning. E.g., DB2 isn’t shared-nothing without this feature.
- IBM is proud of DB2’s compression, which it claims commonly reaches 70-80%. It calls this “industry-leading” in comparison to Oracle, SQL Server, and other general-purpose relational DBMS.
- DB2 compression’s overall effect on performance stems from a trade-off between I/O (lessened) and CPU burden (increased). For OLTP workloads, this is about a wash. For data warehousing workloads, IBM says 20% performance improvement from compression is average.
- DB2 now has its version of one of my favorite Oracle security features, called Label Based Access Control. A label-control feature can make it much easier to secure data on a row-by-row, value-by-value basis. The obvious big user is national intelligence, followed by financial services. IBM says the health care industry also has interest in LBAC.
- Also in the security area, IBM reworked DB2’s audit feature for 9.5
- I think what I heard in our discussion of DB2 virtualization is:
- Increasingly, IBM is seeing production use of VMware, rather than just test/development.
- IBM believes it is a much closer partner to VMware than Oracle or Microsoft is, because it’s not pushing its own competing technology.
- Generally, virtualization is more important for OLTP workloads than data warehousing ones, because OLTP apps commonly only need part of the resources of a node while data warehousing often wants the whole node.
- AIX data warehousing is an exception. I think this is because AIX equates to big SMP boxes, and virtualization lets you spread out the data warehousing processing across more nodes, with the usual parallel I/O benefits.
- When IBM talks of new autonomic/self-tuning features in DB2, they’re used mainly for databases under 1 terabyte in size. Indeed, the self-tuning feature set doesn’t work with InfoSphere Warehouse.
- Even with the self-tuning feature it sounds as if you need at least a couple of DBA hours per instance per week, on average.
- DB2 on Linux/Unix/Windows has introduced some enhanced workload management features analogous to those long found in mainframe DB2. For example, resource allocation rules can be scheduled by time. (The point of workload management is to allocate resources such as CPU or I/O among the simultaneous queries or other tasks that contend for them.) Workload management rules can have thresholds for amounts of resources consumed, after which the priority for a task can go up (“Get it over with!”) or down (“Stop hogging my system!”).
| Categories: Application areas, Data warehousing, Database compression, IBM and DB2, Market share and customer counts, OLTP, Parallelization, Workload management | 2 Comments |
MySQL miscellany
For a guy who doesn’t go to the MySQL conference and routinely gets flamed by the MySQL community for being insufficiently adoring of their beloved product, I sure have been putting up a lot of MySQL-related posts recently. Here’s another, zooming through a few different topics. Read more
| Categories: MySQL, Open source | 4 Comments |
I don’t see why the GPL would be a major barrier to a useful MySQL fork
I posted suggesting that substantial elements of the MySQL community should throw their weight behind MySQL forks. Mike Olson of Cloudera helpfully pointed out, on Twitter and by email, how the GPL could appear to stand in the way of such an effort. But would it really?
Currently, any version of the MySQL code that isn’t proprietary to the MySQL company — which is owned by Sun and hence expected to be owned soon by Oracle — is covered by GPL 2. That license states (emphasis mine):
Activities other than copying, distribution and modification are not covered by this License; they are outside its scope. The act of running the Program is not restricted,
Hence it is hard for me to see how the MySQL company could in any way hinder another software vendor from saying “Please buy my software, then go download a free copy of GPLed MySQL and run the two together.”*
| Categories: MySQL, Open source | 14 Comments |