[jira] [Created] (IGNITE-10852) [Documentation] - Add details on to public API behaviour

[Alexander Gerus (JIRA)]

Alexander Gerus created IGNITE-10852:


 Summary: [Documentation] - Add details on to public API behaviour
 Key: IGNITE-10852
 URL: https://issues.apache.org/jira/browse/IGNITE-10852
 Project: Ignite
  Issue Type: Improvement
  Components: documentation
Affects Versions: 2.7, 2.6, 2.5, 2.4
Reporter: Alexander Gerus


Current public API documentation has some specification gaps. In case if method 
was not successfully executed, it is not clear what should be done by user code.

Good practice is to describe all API exceptions that can be processed by user 
code and recommended actions



--
This message was sent by Atlassian JIRA
(v7.6.3#76005)

RE: REST GridCacheCommandHandler writes ERROR in log in caseofbaduser input

[Gerus]

I think that this case is serious gap in Ignite maintainability
1. This is business as usual case and client application can create an
incorrect API call. User error should be returned back to user via the same
API
2. Exception in the Ignite log file should cause an alert for application
operations. Most common case for monitoring setup is to parse log file in
realtime and create an incident in case if ERROR or Exception is detected.
The only way for admin is to mute the false alert, and 
3. Current approach is adding a lot of noise into the application logs and
significantly increasing logfile size. Taking in account log rotation as a
good practice, we may have less useful information to maintain Ignite



--
Sent from: http://apache-ignite-developers.2346864.n4.nabble.com/

Re: Pre-touch for Ignite off-heap memory

[Gerus]

Hi, Ivan
Let me try to explain. I think that there are 2 goals that are mostly
applicable for prod systems:
1. I can agree with Dave that swap is not a good case for performance and
disk resource. It is possible that other applications can consume memory
that is free after Ignite was started. In this case if Ignite will be
creating new pages in runtime, it can face with OOM. 

2. Ignite user can create wrong configuration. For example, data region can
exceed available memory by mistake or Ignite can be started on another
server with less RAM. It can lead to catch OOM in runtime

To summarize: Pre-allocation can detect listed issues on Ignite start by
allocating OS RAM

Im sure that this option have to be disabled by default, but user should
have a choice for startup



--
Sent from: http://apache-ignite-developers.2346864.n4.nabble.com/

Pre-touch for Ignite off-heap memory

[Gerus]

Hi *Igniters*,
Some time ago I've raised a suggestion for product improvement
https://issues.apache.org/jira/browse/IGNITE-9112
  .  It's all about
off-heap memory allocation. Current implementation can have some
improvements for failure critical systems. Ignite can have OOM in runtime,
because RAM can be used by OS, if it will not be pre-booked by operation
system and this proposal is to address that. Common case is offheap and
thats why memory segment cannot be managed by JVM that has +AlwaysPreTouch
option
Obviously this implementation will make startup longer and thats why it is
proposed to use configuration flag to manage this feature
I think, it will be useful to have this option. Are you supporting this?



--
Sent from: http://apache-ignite-developers.2346864.n4.nabble.com/

[jira] [Created] (IGNITE-9495) Update version for org.apache.lucene lucene-queryparser : 5.5.2

[Alexander Gerus (JIRA)]

Alexander Gerus created IGNITE-9495:
---

 Summary: Update version for org.apache.lucene lucene-queryparser : 
5.5.2
 Key: IGNITE-9495
 URL: https://issues.apache.org/jira/browse/IGNITE-9495
 Project: Ignite
  Issue Type: Improvement
Affects Versions: 2.6, 2.5, 2.4
Reporter: Alexander Gerus


Update version for org.apache.lucene
Current version: lucene-queryparser : 5.5.2
New version version: later than 7.1



--
This message was sent by Atlassian JIRA
(v7.6.3#76005)

[jira] [Created] (IGNITE-9112) Pre-touch for Ignite off-heap memory

[Alexander Gerus (JIRA)]

Alexander Gerus created IGNITE-9112:
---

 Summary: Pre-touch for Ignite off-heap memory
 Key: IGNITE-9112
 URL: https://issues.apache.org/jira/browse/IGNITE-9112
 Project: Ignite
  Issue Type: New Feature
Affects Versions: 2.6, 2.5, 2.4
Reporter: Alexander Gerus


At the moment Ignite off-heap memory is allocated in virtual memory of 
operating system, not physical memory: it is recorded in an internal data 
structure to avoid it being used by any other process. Not even a single page 
will be allocated in physical memory until it's actually accessed. When the 
Ignite needs memory, the operating system will allocate pages as needed.

The proposal is to add an option to Ignite that will touch every single byte of 
the max off heap with a '0', resulting in the memory being allocated in the 
physical memory in addition to being reserved in the internal data structure 
(virtual memory). Similar option is available in JVM {{-XX:+AlwaysPreTouch}}



--
This message was sent by Atlassian JIRA
(v7.6.3#76005)