how to set storage.diskCache.bufferSize

[Mahesh Wabale]

hello every one , 

 I am using orientdb 2.0 snapshot , i want to know about diskcache . If we use plocal storage with enough RAM , how to set diskcache .  I read the doc about performance tuning  http://orientdb.com/docs/last/Performance-Tuning.html#Parameters . But cant able to set diskcache . 

 want to know : 

 1. what are the configuration for diskcache .   ? 

 2. How to check disk cache buffersize after updating the limit ? 

 3. Is it working on distributed database with plocal storage ?

 4. What are the advantages if we use this ?

Thanks in advance ....

  

[David Carr]

Me too

[alessand...@gmail.com]

Hi,

to set for example 1G for the diskcache you must insert the following instruction 

set MAXDISKCACHE=-Xmx1024m 

in the file server.bat or server.sh

Kind regards,

Alessandro

[David Carr]

Alessandro -

For clarification, if I'm running a server daemon and my goal is for OrientDB to use all available memory on the server, how exactly do I set maxdiskcache?

TOP says the following:

top - 11:04:23 up 12:31,  1 user,  load average: 0.00, 0.01, 0.01

Tasks:  79 total,   1 running,  78 sleeping,   0 stopped,   0 zombie

Cpu(s):  0.0%us,  0.0%sy,  0.0%ni,100.0%id,  0.0%wa,  0.0%hi,  0.0%si,  0.0%st

Mem:  31420088k total,   353352k used, 31066736k free,    11864k buffers

Swap:        0k total,        0k used,        0k free,   101032k cached

OPTION A

ASSUMES MAXDISKCACHE MEANS A MAXIMUM AND WE WANT ORIENTDB TO USE ALL AVAILABLE MEMORY AND NOT BE LIMITED TO ANY MAXIMUM. IS THIS WRONG???

# ORIENTDB MAXIMUM HEAP. USE SYNTAX -Xmx<memory>, WHERE <memory> HAS THE TOTAL MEMORY AND SIZE UNIT. EXAMPLE: -Xmx512m

MAXHEAP=-Xmx512m

# ORIENTDB MAXIMUM DISKCACHE IN MB, EXAMPLE, ENTER -Dstorage.diskCache.bufferSize=8192 FOR 8GB

MAXDISKCACHE="" 

OPTION B

30554 = FREE MEMORY OF 310667 - 512 HEAP

# ORIENTDB MAXIMUM HEAP. USE SYNTAX -Xmx<memory>, WHERE <memory> HAS THE TOTAL MEMORY AND SIZE UNIT. EXAMPLE: -Xmx512m

MAXHEAP=-Xmx512m

# ORIENTDB MAXIMUM DISKCACHE IN MB, EXAMPLE, ENTER -Dstorage.diskCache.bufferSize=8192 FOR 8GB

MAXDISKCACHE="-Dstorage.diskCache.bufferSize=30554" 

WHEN I RUN THIS SETTING THERE IS NOT FEEDBACK IN orient-server-log.0 SAYING HOW MUCH MEMORY ORIENTDB WILL USE.

OPTION C

PER YOUR INSTRUCTIONS HERE. IS THIS THE RIGHT SETTING? THE SYNTAX IS VERY DIFFERENT THAN THE EXAMPLE IN THE COMMENT ONE LINE HIGHER.

# ORIENTDB MAXIMUM HEAP. USE SYNTAX -Xmx<memory>, WHERE <memory> HAS THE TOTAL MEMORY AND SIZE UNIT. EXAMPLE: -Xmx512m

MAXHEAP=-Xmx512m

# ORIENTDB MAXIMUM DISKCACHE IN MB, EXAMPLE, ENTER -Dstorage.diskCache.bufferSize=8192 FOR 8GB

MAXDISKCACHE=-Xmx30554m

WHEN I RUN IT WITH THIS SETTING MY orient-server-log.0 SAYS

2015-09-02 11:45:32:349 INFO  OrientDB auto-config DISKCACHE=1,476MB (heap=27,159MB os=30,683MB disk=38,941MB) [orientechnologies]

WHICH DOESN'T LOOK RIGHT TO ME IF MY UNDERSTANDING IS ON TARGET. SETTING -Xmx ONCE WITH MAXHEAP= AND A SECOND TIME WITH MAXDISKCACHE= SEEMS REDUNDANT. ALESSANDRO CAN YOU VERIFY?

IF I'M RUNNING ORIENTDB AS A DAEMON FOR REMOTE ACCESS THEN IS THE BEST THING TO PUT ALL AVAILABLE MEMORY INTO HEAP SPACE? OR SPLIT IT WITH DISKCACHE? AT http://orientdb.com/docs/2.1/Performance-Tuning.html IT SAYS TO KEEP HEAP RELATIVELY LOW AND DISKCACHE HIGH BUT IT'S NOT CLEAR UNDER WHAT CIRCUMSTANCES.

 

OPTION D

Other???

Thank you in advance for your help! It is very confusing to navigate these performance-tuning issues.