3 ms·

Rant warning: After working with Neo4j for about six months I would definitely NOT recommend it to anyone. In my experience it has been the least reliable and

Rant warning: After working with Neo4j for about six months I would definitely NOT recommend it to anyone. In my experience it has been the least reliable and most buggy database solution I've ever worked with. From the engineering point of view it has a host of core issues that make it really hard to write code, such as constant deadlock exceptions. These are caused by the fact that the database is largely incapable of handling two simultaneous upserts if those upserts touch the same node. Where most mature, decent DBs can handle this completely transparently Neo4j just panics and returns an error. This means writing Neo4j queries ends up requiring tons of boilerplate to wait for exclusive locks on nodes and/or retry upserts until they succeed. From the devops perspective managing a cluster is also extremely painful, as there are frequent issues with replicas getting behind on syncing due to the server's pathetically slow write performance even with SSD storage volumes. We tried everything but the bottleneck was the server processes themselves, not the storage volumes, network connection, CPU, etc. We threw some really nice hardware at our Neo4j cluster but it still struggled to keep up with write loads in the range of 500-2000 writes per minute. The final straw was their latest version 2.2 which they were advertising as a massive improvement in speed and reliability. When we upgraded it turned out to be the exact opposite. A few of our queries got faster but overall most of them got an order of magnitude slower. Their support basically told us that we'd need to rewrite many of our queries or manually set a flag to use their older query engine (and therefore miss out on the speed of the new query engine). Needless to say we decided if we needed to rewrite queries we were going to rewrite them to use a different storage engine entirely. In my experience Neo4j was little more than a six month waste of time and dev resources.

mrits 11y ago
Haha, damn... That sounds pretty harsh. Neo4J seems really interesting to me. Who doesn't want to get better with graphs? I still want to learn the query language as it is applicable to some of the problems I'm trying to solve now. This isn't the first horror story I've heard about Neo4J so I've actually stayed away from using it professionally.
don71 11y ago
Hi, I'm Claudius, the author of the blog post. The intent of the blog was not to show, that a particular product is not performing well. There are thousands of different use cases and each database has its strengths and weaknesses. For a different scenario the results might be different. Neo4J is a solid product and is doing a good job. The aim of the blog was to show, that multi-model can compete with specialized solutions. What I wanted to show, is that a multi-model approach per se does not carry a performance penalty.
- rspeer 11y ago
  > Neo4J is a solid product Do you really believe this, in your expert opinion, or are you just trying not to step on toes?
  - don71 11y ago
    We are a multi-model database, which is not in a strict sense a competitor but is competing with Neo4J in some areas. Therefore I'm definitely not a Neo4J expert. However, I'm now working in the field for over 15 years, developing in-memory solutions, databases and application servers. Developing ArangoDB for almost three years and I have talked to a lot of people in that area and to people who are using Neo4J. There are always obstacle when moving to new products. But most of the people who I met are quite happy with Neo4J.
- NathanKP 11y ago
  > Neo4j is a solid product and is doing a good job. My personal opinion, based on my experiences using Neo4j, is that Neo4j is not a solid product. (At least not by my definition of "solid".) I think it has good marketing but falls apart in a lot of real world use cases. I understand that the point of the blog post wasn't to bash Neo4j, but it does demonstrate quite well the fact that a multi model approach can be quite competitive or even better in terms of performance for many use cases. Given Neo4j's historical and ongoing issues, if the multi model DB solution also happens to be a more mature and stable one then there is no front on which Neo4j wins.
rspeer 11y ago
I had a pretty similar experience, in fact. I lost months of work to Neo4J back in 2011 or so. The purpose was to be the storage backend for ConceptNet, a semantic network that is largish but is far from "big data". The write speed was awful, the stability was awful, the mechanisms for loading in non-toy amounts of data were nearly nonexistent, and I learned what it means to "run out of PermGen". I hastily aborted the Neo4J plan. I was also burned by RDF triple-stores (they can't cope with small data either) and MongoDB (which seemed to work at first and eventually fell over, for obvious reasons in retrospect). The graph is now in SQLite plus flat files, which works great. I've concluded by now that the step on the scale beyond "lies" and "damn lies" is "claims about next-generation databases".
gmarx 11y ago
Good to hear because I started to experiment with it a couple months ago to solve a specific problem. I abandoned it because the embedded version required an older version of Lucene than I was using. Yes I could have worked around that but it's a lot of extra work to try something that may or may not solve my problem. Then I tried the server version which also required I be able to call web services (something my code had no other use for). Worked through that and found the performance pretty poor compared to embedded. I ended up just solving the problem in Lucene. Glad I didn't spend more time on it. I would love to have a good graph database later on though
shiv86 11y ago
So what did you end up doing with it ? ... How did you replace it ?

mrits 11y ago

Haha, damn... That sounds pretty harsh. Neo4J seems really interesting to me. Who doesn't want to get better with graphs? I still want to learn the query language as it is applicable to some of the problems I'm trying to solve now. This isn't the first horror story I've heard about Neo4J so I've actually stayed away from using it professionally.

don71 11y ago

Hi, I'm Claudius, the author of the blog post. The intent of the blog was not to show, that a particular product is not performing well. There are thousands of different use cases and each database has its strengths and weaknesses. For a different scenario the results might be different. Neo4J is a solid product and is doing a good job. The aim of the blog was to show, that multi-model can compete with specialized solutions. What I wanted to show, is that a multi-model approach per se does not carry a performance penalty.

rspeer 11y ago
> Neo4J is a solid product Do you really believe this, in your expert opinion, or are you just trying not to step on toes?
- don71 11y ago
  We are a multi-model database, which is not in a strict sense a competitor but is competing with Neo4J in some areas. Therefore I'm definitely not a Neo4J expert. However, I'm now working in the field for over 15 years, developing in-memory solutions, databases and application servers. Developing ArangoDB for almost three years and I have talked to a lot of people in that area and to people who are using Neo4J. There are always obstacle when moving to new products. But most of the people who I met are quite happy with Neo4J.
NathanKP 11y ago
> Neo4j is a solid product and is doing a good job. My personal opinion, based on my experiences using Neo4j, is that Neo4j is not a solid product. (At least not by my definition of "solid".) I think it has good marketing but falls apart in a lot of real world use cases. I understand that the point of the blog post wasn't to bash Neo4j, but it does demonstrate quite well the fact that a multi model approach can be quite competitive or even better in terms of performance for many use cases. Given Neo4j's historical and ongoing issues, if the multi model DB solution also happens to be a more mature and stable one then there is no front on which Neo4j wins.

rspeer 11y ago

I had a pretty similar experience, in fact. I lost months of work to Neo4J back in 2011 or so. The purpose was to be the storage backend for ConceptNet, a semantic network that is largish but is far from "big data". The write speed was awful, the stability was awful, the mechanisms for loading in non-toy amounts of data were nearly nonexistent, and I learned what it means to "run out of PermGen". I hastily aborted the Neo4J plan. I was also burned by RDF triple-stores (they can't cope with small data either) and MongoDB (which seemed to work at first and eventually fell over, for obvious reasons in retrospect). The graph is now in SQLite plus flat files, which works great. I've concluded by now that the step on the scale beyond "lies" and "damn lies" is "claims about next-generation databases".

gmarx 11y ago

Good to hear because I started to experiment with it a couple months ago to solve a specific problem. I abandoned it because the embedded version required an older version of Lucene than I was using. Yes I could have worked around that but it's a lot of extra work to try something that may or may not solve my problem. Then I tried the server version which also required I be able to call web services (something my code had no other use for). Worked through that and found the performance pretty poor compared to embedded. I ended up just solving the problem in Lucene. Glad I didn't spend more time on it. I would love to have a good graph database later on though

shiv86 11y ago

So what did you end up doing with it ? ... How did you replace it ?