LruCache

[Eugeny Kozhanov]

I use Lru cache in my plugin:

LruCache<String, List<String>> lruc = new LruCache<String, List<String>>("myLruCache", 1);

Why cache is flushing before each request of my plugin method?

[Mattias Persson]

You pass in 1 in the constructor... that is maxSize=1, which pretty much makes your LruCache equivalent to a String reference to the last string inserted into it.

2012/10/1 Eugeny Kozhanov <vin...@gmail.com>

I use Lru cache in my plugin:

LruCache<String, List<String>> lruc = new LruCache<String, List<String>>("myLruCache", 1);

Why cache is flushing before each request of my plugin method?

--
 
 

--
Mattias Persson, [mat...@neotechnology.com]
Hacker, Neo Technology
www.neotechnology.com

[Eugeny Kozhanov]

thanks! I set 1000.

Did LRU cache use follow parameters:

node_cache_size = 2G

relationship_cache_size = 1G

?

[Mattias Persson]

No, those are only used by the "gcr" cache, available in the enterprise packaging of neo4j.

2012/10/1 Eugeny Kozhanov <vin...@gmail.com>

[Eugeny Kozhanov]

Can I know cache used memory?

[Eugeny Kozhanov]

value of used memory (in megabytes, for example)

[Mattias Persson]

No, it doesn't tell you that, just how many items it has, via the size() method.

2012/10/1 Eugeny Kozhanov <vin...@gmail.com>

[Eugeny Kozhanov]

Thank you! I try use it.

[Eugeny Kozhanov]

and some small question: this cache use RAM? it's included into Java Heap Space?

[Mattias Persson]

2012/10/1 Eugeny Kozhanov <vin...@gmail.com>

and some small question: this cache use RAM? it's included into Java Heap Space?

Yes

[Eugeny Kozhanov]

Thanks a lot!

[Eugeny Kozhanov]

Cache will flush after stop server. Can I save this to file? How I read this from file before restart the server?

[Mattias Persson]

The LruCache class in neo4j is merely a wrapped LinkedHashMap, there's nothing more fancy to it I'm afraid.

2012/10/2 Eugeny Kozhanov <vin...@gmail.com>

[Michael Hunger]

If you need something like that, then dumping the content (ie. keys & node-id's) of the cache to a file and repopulating it at startup should be easy for you.

Michael

--
 
 

[Eugeny Kozhanov]

That is good idea, thanks!