Is salesforce.com going to stick with Oracle?
Surprisingly often, I’m asked “Is salesforce.com going to stick with Oracle?” So let me refer to and expand upon my previous post about salesforce.com’s database architecture by saying:
- Today, salesforce.com uses Oracle as one of several ways to store data.
- salesforce.com’s use of Oracle isn’t very relational.
- salesforce.com is investing in HBase, after exploring other NoSQL options.
- salesforce.com surely has a very inexpensive Oracle license, reducing pressure to move any time soon. However …
- … salesforce.com’s use of Oracle has flipped from being a marketing advantage to a marketing liability.*
- It will be some years before any NoSQL option is mature enough to handle salesforce.com’s work.
- Especially through Heroku, salesforce.com is getting ever more experience with PostgreSQL.
Some day, Marc Benioff will probably say “We turned off Oracle across most of our applications a while ago, and nobody outside the company even noticed.”
*in that
- The marketing benefit “Oracle — it’s what the trustworthy big boys use” hardly matters any more.
- The marketing annoyance of Larry Ellison citing salesforce.com’s use of Oracle keeps growing.
Note: This blog post is less readable than it would be if I’d found a better workaround to WordPress’ bugs in the area of nested bullet points. I’m sorry.
| Categories: NoSQL, OLTP, Oracle, salesforce.com, Software as a Service (SaaS) | 10 Comments |
Teradata SQL-H, using HCatalog
When I grumbled about the conference-related rush of Hadoop announcements, one example of many was Teradata Aster’s SQL-H. Still, it’s an interesting idea, and a good hook for my first shot at writing about HCatalog. Indeed, other than the Talend integration bundled into Hortonworks’ HDP 1, Teradata SQL-H is the first real use of HCatalog I’m aware of.
The Teradata SQL-H idea is:
- Register your Hadoop data to HCatalog. I’ll confess to being unclear about the details of how that works, for example in the case of data that just doesn’t fit well into flat relational tables. Stay tuned for future posts. For now, I’ll just note that:
- HCatalog is closely based on Hive’s metadata management. If you’ve run Hive against the data, HCatalog should already know about it.
- HCatalog can handle Pig and HBase data as well.
- Write SQL DDL (Data Description Language) so that your Aster cluster knows about the data.
- Write any Teradata Aster SQL/MR against that data. Some of the execution will be done on the Hadoop cluster, but pulling data back into Aster may well be necessary.
At least in theory, Teradata SQL-H lets you use a full set of analytic tools against your Hadoop data, with little limitation except price and/or performance. Teradata thinks the performance of all this can be much better than if you just use Hadoop (35X was mentioned in one particularly favorable example), but perhaps much worse than if you just copy/extract the data to an Aster cluster in the first place.
So what might the use cases be for something like SQL-H? Offhand, I’d say:
- SQL-H use cases are probably focused in areas where copying the data to Aster in advance doesn’t make a lot of sense. So presumably …
- … the Hadoop clusters involved would hold a lot more data than you’d want to pay for storing in Teradata Aster. E.g., think of cases where Hadoop is used as a big bit bucket or archival data store.
- There could be a kind of investigative workflow. First you play around with the Hadoop data via SQL-H. Then when you think you’re onto something, you set up ETL (Extract/Transform/Load) to get the data into Aster and ratchet up the effort.
By way of contrast, the whole thing makes less sense for dashboarding kinds of uses, unless the dashboard users are very patient when they want to drill down.
Why I’m so forward-leaning about Hadoop features
In my recent series of Hadoop posts, there were several cases where I had to choose between recommending that enterprises:
- Go with the most advanced features any vendor was credibly advocating.
- Be more cautious, and only adopt features that have been solidly proven in the field.
I favored the more advanced features each time. Here’s why.
To a first approximation, I divide Hadoop use cases into two major buckets, only one of which I was addressing with my comments:
1. Analytic data management.* Here I favored features over reliability because they are more important, for Hadoop as for analytic RDBMS before it. When somebody complains about an analytic data store not being ready for prime time, never really working, or causing them to tear their hair out, what they usually mean is that:
- It couldn’t do the work that needed doing …
- … with reasonable performance and turnaround time …
- … without undue effort in administration and/or programming.
Those complaints are much, much, more frequent than “It crashed”. So it was for Netezza, DATAllegro, Greenplum, Aster Data, Vertica, Infobright, et al. So it also is for Hadoop. And how does one address those complaints? By performance and feature enhancements, of the kind that the Hadoop community is introducing at high speed. Read more
| Categories: Buying processes, Data warehousing, EAI, EII, ETL, ELT, ETLT, Hadoop, HBase, Hortonworks, Open source | 1 Comment |
Notes on HBase 0.92
This is part of a four-post series, covering:
- Annoying Hadoop marketing themes that should be ignored.
- Hadoop versions and distributions, and their readiness or lack thereof for production.
- In general, how “enterprise-ready” is Hadoop?
- HBase 0.92 (this post)
As part of my recent round of Hadoop research, I talked with Cloudera’s Todd Lipcon. Naturally, one of the subjects was HBase, and specifically HBase 0.92. I gather that the major themes to HBase 0.92 are:
- Performance, scalability, and so on.
- “Coprocessors”, which are like triggers or stored procedures.
- Security, as the first major application of co-processors.
HBase coprocessors are Java code that links straight into HBase. As with other DBMS extensions of the “links straight into the DBMS code” kind,* HBase coprocessors seem best suited for very sophisticated users and third parties.** Evidently, coprocessors have already been used to make HBase security more granular — role-based, per-column-family/per-table, etc. Further, Todd thinks coprocessors could serve as a good basis for future HBase enhancements in areas such as aggregation or secondary indexing. Read more
| Categories: Benchmarks and POCs, Cloudera, Hadoop, HBase, MapReduce, NoSQL, Open source, Storage, Theory and architecture | 2 Comments |
“Enterprise-ready Hadoop”
This is part of a four-post series, covering:
- Annoying Hadoop marketing themes that should be ignored.
- Hadoop versions and distributions, and their readiness or lack thereof for production.
- In general, how “enterprise-ready” is Hadoop (this post)?
- HBase 0.92.
The posts depend on each other in various ways.
Cloudera, Hortonworks, and MapR all claim, in effect, “Our version of Hadoop is enterprise-ready, unlike those other guys’.” I’m dubious.
- Hortonworks has considerably fewer features than Cloudera, along with less of a production or support track record. (Edit: HCatalog may be a significant exception.)
- I doubt Cloudera really believes or can support the apparent claim in its CDH 4 press release that Hadoop is now suitable for every enterprise, whereas last month it wasn’t.
- While MapR was early with some nice enterprise features, such as high availability or certain management UI elements — quickly imitated in Cloudera Enterprise — I don’t think it has any special status as “enterprise-ready” either.
That said, “enterprise-ready Hadoop” really is an important topic.
So what does it mean for something to be “enterprise-ready”, in whole or in part? Common themes in distinguishing between “enterprise-class” and other software include:
- Usable by our existing staff.
- Sufficiently feature-rich.
- Integrates well with the rest of our environment.
- Fits well into our purchasing and vendor relations model.
- Well-supported.
- Sufficiently reliable, proven, and secure — which is to say, “safe”.
For Hadoop, as for most things, these concepts overlap in many ways. Read more
| Categories: Buying processes, Cloudera, Clustering, Hadoop, HBase, Hortonworks, MapR, MapReduce, Open source | 9 Comments |
Hadoop distributions: CDH 4, HDP 1, Hadoop 2.0, Hadoop 1.0 and all that
This is part of a four-post series, covering:
- Annoying Hadoop marketing themes that should be ignored.
- Hadoop versions and distributions, and their readiness or lack thereof for production (this post).
- In general, how “enterprise-ready” is Hadoop?
- HBase 0.92.
The posts depend on each other in various ways.
My clients at Cloudera and Hortonworks have somewhat different views as to the maturity of various pieces of Hadoop technology. In particular:
- Cloudera introduced CDH 4* and Hortonworks introduced HDP 1*, both timed for the recent Hadoop Summit.
- CDH 4 is based mainly on Hadoop 2.0, which Cloudera says it has tested extensively.
- HDP 1 is based on Hadoop 1.0, on the theory that nobody has properly tested Hadoop 2.0, which is still characterized as “alpha”.
- CDH 4 boasts sub-second NameNode failover.
- Hortonworks is partnering with third parties such as VMware to address the high-availability problems caused by failover potentially taking several minutes.
- Hadoop 2.0 and CDH 4 also incorporate improvements to NameNode scalability, HDFS (Hadoop Distributed File System) performance, HBase performance, and HBase functionality.
- As does CDH 4, HDP 1 includes HCatalog, an extension of Hive technology that serves as a more general metadata store. (Edit: Actually, see the comment thread below.)
- Hortonworks thinks HCatalog is a big deal in improving Hadoop data management and connectivity, and already has a Talend partnership based on HCatalog. Cloudera is less sure, especially in HCatalog’s current form.
- HDP 1 includes Ambari, an Apache open source competitor to Cloudera Manager (the closed-source part of Cloudera Enterprise). Hortonworks concedes a functionality gap between Ambari and Cloudera Manager, but perhaps a smaller one than Cloudera sees.
- Hortonworks thinks Ambari being open source means better integration with other management platforms. Cloudera touts the integration features and integrations of Cloudera Manager 4.
- Nobody seems confident that MapReduce 2 is ready for prime time. While it’s in CDH 4, so is MapReduce 1.
*”CDH” stands, due to some trademarking weirdness, for “Cloudera’s Distribution including Apache Hadoop”. “HDP” stands for “Hortonworks Data Platform”.
| Categories: Amazon and its cloud, Cloudera, Hadoop, Hortonworks, MapReduce, Market share and customer counts | 14 Comments |
Hadoop marketing themes that deserve to be ignored
This is part of a four-post series, covering:
- Annoying Hadoop marketing themes that should be ignored (this post).
- Hadoop versions and distributions, and their readiness or lack thereof for production.
- In general, how “enterprise-ready” is Hadoop?
- HBase 0.92.
The posts depend on each other in various ways.
I am subjected to much Hadoop marketing. Indeed, I even help various clients inflict Hadoop marketing upon the world. But a guy’s got to draw a line somewhere, and there are certain Hadoop marketing themes that I just refuse to take seriously.
1. Big data. I think the term “big data” long ago jumped the shark. If a firm uses the term “big data”, I teeth-grittingly let it pass. But if they send me PR email offering to “explain” the benefits or “real meaning” of “big data”, my response is apt to be unkind.
2. Conference-timed news. I’ve never liked the custom of multiple vendors piling announcements into the same conference week. It seems like a calculated strategy to ensure getting the least possible mind share and attention — unless, of course, your announcement is so lame that brief mentions in conference-week roundups are the most visibility you can hope to get. Even so, many vendors make the marketing choice to pile on. Fine. But I’ll write in response if and when I feel like it.
3. Contribution Olympics. The Urinary Olympics as to who contributed more lines of code, patches, whatever to various Hadoop sub-projects got pretty silly; and although it peaked last year, elements of it are with us still. I do see two scenarios where the whole discussion might have genuine value, namely:
- When two vendors — typically Hortonworks and Cloudera — differ about a particular Hadoop sub-project, I’m inclined to believe the one who asserts “Well, we built most of and then extensively tested the last release of this, and it does what we say it does.”
- If you have a specialized desire to see a particular aspect of Hadoop hacked, there are a limited number of developers who are best-suited to do it for you, and you might be best served to deal with the company that employs (most of) them.
Otherwise, however, I pay little attention to claims like “We thought this scheme up 2 years ago, and hence we’re the experts on whether it’s now ready for production.”
| Categories: Cloudera, Hadoop, Hortonworks | 12 Comments |
Introduction to MemSQL
I talked with MemSQL shortly before today’s launch. MemSQL technology basics are:
- In-memory relational DBMS.
- Being released single-box only. Transparent sharding is under development for release in the fall. Basic replication is under development too.
- Subset of SQL-92.
- MySQL wire-compatible (SQL coverage issues excepted).
MemSQL’s performance claims include:
- Read performance 10% or so worse than memcached.
- Write performance 20% or so better than memcached.
- 1.2 million inserts/second on a 64-core, 1/2 TB of RAM machine.
- Similarly, 1/2 billion records loaded in under 20 minutes.
MemSQL company basics include: Read more
| Categories: Database compression, In-memory DBMS, Investment research and trading, Market share and customer counts, memcached, MemSQL, OLTP, Pricing, Web analytics | 3 Comments |
Metamarkets’ back-end technology
This is part of a three-post series:
- Introduction to Metamarkets and Druid
- Druid overview
- Metamarkets’ back-end technology (this post)
The canonical Metamarkets batch ingest pipeline is a bit complicated.
- Data lands on Amazon S3 (uploaded or because it was there all along).
- Metamarkets processes it, primarily via Hadoop and Pig, to summarize and denormalize it, and then puts it back into S3.
- Metamarkets then pulls the data into Hadoop a second time, to get it ready to be put into Druid.
- Druid is notified, and pulls the data from Hadoop at its convenience.
By “get data read to be put into Druid” I mean:
- Build the data segments (recall that Druid manages data in rather large segments).
- Note metadata about the segments.
That metadata is what goes into the MySQL database, which also retains data about shards that have been invalidated. (That part is needed because of the MVCC.)
By “build the data segments” I mean:
- Make the sharding decisions.
- Arrange data columnarly within shard.
- Build a compressed bitmap for each shard.
When things are being done that way, Druid may be regarded as comprising three kinds of servers: Read more
Metamarkets Druid overview
This is part of a three-post series:
- Introduction to Metamarkets and Druid
- Druid overview (this post)
- Metamarkets’ back-end technology
My clients at Metamarkets are planning to open source part of their technology, called Druid, which is described in the Druid section of Metamarkets’ blog. The timing of when this will happen is a bit unclear; I know the target date under NDA, but it’s not set in stone. But if you care, you can probably contact the company to get involved earlier than the official unveiling.
I imagine that open-source Druid will be pretty bare-bones in its early days. Code was first checked in early in 2011, and Druid seems to have averaged around 1 full-time developer since then. What’s more, it’s not obvious that all the features I’m citing here will be open-sourced; indeed, some of the ones I’m describing probably won’t be.
In essence, Druid is a distributed analytic DBMS. Druid’s design choices are best understood when you recall that it was invented to support Metamarkets’ large-scale, RAM-speed, internet marketing/personalization SaaS (Software as a Service) offering. In particular:
- Druid tries to use RAM well.
- Druid tries to stay up all the time.
- Druid has multi-valued fields. (Numeric, but of course you can use encoding tricks to be effectively more general.)
- Druid’s big limitation is to assume that there’s literally only one (denormalized) table per query; you can’t even join to dimension tables.
- SQL is a bit of an afterthought; I would expect Druid’s SQL functionality to be pretty stripped-down out of the gate.
Interestingly, the single-table/multi-valued choice is echoed at WibiData, which deals with similar data sets. However, WibiData’s use cases are different from Metamarkets’, and in most respects the WibiData architecture is quite different from that of Metamarkets/Druid.