Re: Enabling swapPath causes invoking shutdown hook

[Denis Magda]

If Ignite can hold all the records in memory it won't be reading pages from
disk (the page replacement). Thus, it's expected that the 12GB performs
better than the 5GB case.

Btw, are you planning to reload the whole data set into Ignite on potential
cluster restarts? Each node loses a subset of the data located in the swap
space on restarts.

-
Denis


On Thu, Aug 13, 2020 at 7:36 PM 38797715 <38797...@qq.com> wrote:

> Hi Denis,
>
> We did a test, in the same environment (8G RAM, 10G swap partition) and
> the same configuration (2G Heap, enable persistence, data volume is about
> 6G), the only difference is that the maxSize size is different, which is
> configured as 5G and 12G respectively. We found that the performance of the
> scenario with maxSize = 12G is better than that of the scenario with
> maxSize = 5G, and the write performance is improved by more than 10%.
>
> I suspect that if the memory data region is large enough to hold all the
> data, ignite's page replacement might not be enabled.
>
> Our test scenarios are limited and may not be convincing. However, I think
> that the lack of memory may be the norm. At this time, it may be a good
> practice to make full use of the swap mechanism of the OS, which takes up
> more disk space but achieves better performance.
> 在 2020/8/14 上午8:22, Denis Magda 写道:
>
> Ignite swapping is based on the swapping mechanism of the OS. So, you
> shouldn’t see any difference if enable the OS one directly some way.
>
> Generally, you should not use swapping of any form as a permanent
> persistence layer due to the performance penalty. Once the swapping kicks
> in, you should scale out your cluster and wait while the cluster rebalances
> a part of the data to a new node. When the rebalancing completes, the
> performance will be recovered and swapping won’t longer be needed.
>
> Denis
>
> On Thursday, August 13, 2020, 38797715 <38797...@qq.com> wrote:
>
>> Hi,
>>
>> We retested and found that if we configured swapPath, as the amount of
>> data increased, the write speed was actually slower and slower. If the
>> amount of data is large, on average, it is much slower than the scenario
>> where native persistence is enabled and wal is disabled.
>>
>> In this way, the use of the swapPath property has no productive value,
>> maybe it was an early development function, and now it is a bit out of date.
>>
>> What I want to ask is, in the case of small physical memory, turning on
>> persistence, and then configuring a larger maxSize (using the swap
>> mechanism of the OS), is this a solution? In other words, the swap
>> mechanism of the OS and the page replacement of Ignite, which is better?
>> 在 2020/8/6 下午9:23, Ilya Kasnacheev 写道:
>>
>> Hello!
>>
>> I think the performance of swap space should be on par with persistence
>> with disabled WAL.
>>
>> You can submit suggested updates to the documentation if you like.
>>
>> Regards,
>> --
>> Ilya Kasnacheev
>>
>>
>> ср, 5 авг. 2020 г. в 06:00, 38797715 <38797...@qq.com>:
>>
>>> Hi Ilya,
>>>
>>> If so, there are two ways to implement ignite's swap space:
>>> 1. maxSize > physical memory, which will use the swap mechanism of the
>>> OS, can be used *vm.swappiness* Adjust.
>>> 2. Configure the *swapPath* property, which is implemented by Ignite
>>> itself, is independent of the OS and has no optimization parameters.
>>> There's a choice between these two models, right? Then I think there may
>>> be many problems in the description of the document. I hope you can check
>>> it again:
>>> https://apacheignite.readme.io/docs/swap-space
>>>
>>> After our initial testing, the performance of swap space is much better
>>> than native persistence, so I think this pattern is valuable in some
>>> scenarios.
>>> 在 2020/8/4 下午10:16, Ilya Kasnacheev 写道:
>>>
>>> Hello!
>>>
>>> From the docs:
>>>
>>> To avoid this situation with the swapping capabilities, you need to :
>>>
>>>- Set maxSize = bigger_ than_RAM_size, in which case, the OS will
>>>take care of the swapping.
>>>- Enable swapping by setting the DataRegionConfiguration.swapPath
>>> property.
>>>
>>>
>>> I actually think these are either-or. You should either do the first
>>> (and configure OS swapping) or the second part.
>>>
>>> Having said that, I recommend setting proper Native Persistence instead.
>>>
>>> Regards,
>>> --
>>> Ilya Kasnacheev
>>>
>>>
>>> сб, 25 июл. 2020 г. в 04:49, 38797715 <38797...@qq.com>:
>>>
 Hi,

 https://apacheignite.readme.io/docs/swap-space

 According to the above document, if the physical memory is small, you
 can solve this problem by opening the swap space,The specific method is to
 configure maxSize to a larger value (i.e. larger than the physical memory),
 and the swapPath property needs to be configured.

 But from the test results, the node is terminated.

 I think the correct result should be that even if the amount of data
 exceeds the physical memory, the node should still be able 

Re: Enabling swapPath causes invoking shutdown hook

[38797715]

Hi Denis,

We did a test, in the same environment (8G RAM, 10G swap partition) and 
the same configuration (2G Heap, enable persistence, data volume is 
about 6G), the only difference is that the maxSize size is different, 
which is configured as 5G and 12G respectively. We found that the 
performance of the scenario with maxSize = 12G is better than that of 
the scenario with maxSize = 5G, and the write performance is improved by 
more than 10%.


I suspect that if the memory data region is large enough to hold all the 
data, ignite's page replacement might not be enabled.


Our test scenarios are limited and may not be convincing. However, I 
think that the lack of memory may be the norm. At this time, it may be a 
good practice to make full use of the swap mechanism of the OS, which 
takes up more disk space but achieves better performance.


在 2020/8/14 上午8:22, Denis Magda 写道:
Ignite swapping is based on the swapping mechanism of the OS. So, you 
shouldn’t see any difference if enable the OS one directly some way.


Generally, you should not use swapping of any form as a permanent 
persistence layer due to the performance penalty. Once the swapping 
kicks in, you should scale out your cluster and wait while the cluster 
rebalances a part of the data to a new node. When the rebalancing 
completes, the performance will be recovered and swapping won’t longer 
be needed.


Denis

On Thursday, August 13, 2020, 38797715 <38797...@qq.com 
> wrote:


Hi,

We retested and found that if we configured swapPath, as the
amount of data increased, the write speed was actually slower and
slower. If the amount of data is large, on average, it is much
slower than the scenario where native persistence is enabled and
wal is disabled.

In this way, the use of the swapPath property has no productive
value, maybe it was an early development function, and now it is a
bit out of date.

What I want to ask is, in the case of small physical memory,
turning on persistence, and then configuring a larger maxSize
(using the swap mechanism of the OS), is this a solution? In other
words, the swap mechanism of the OS and the page replacement of
Ignite, which is better?

在 2020/8/6 下午9:23, Ilya Kasnacheev 写道:

Hello!

I think the performance of swap space should be on par with
persistence with disabled WAL.

You can submit suggested updates to the documentation if you like.

Regards,
-- 
Ilya Kasnacheev



ср, 5 авг. 2020 г. в 06:00, 38797715 <38797...@qq.com
>:

Hi Ilya,

If so, there are two ways to implement ignite's swap space:
1. maxSize > physical memory, which will use the swap
mechanism of the OS, can be used *vm.swappiness* Adjust.
2. Configure the *swapPath* property, which is implemented by
Ignite itself, is independent of the OS and has no
optimization parameters.

There's a choice between these two models, right? Then I
think there may be many problems in the description of the
document. I hope you can check it again:
https://apacheignite.readme.io/docs/swap-space


After our initial testing, the performance of swap space is
much better than native persistence, so I think this pattern
is valuable in some scenarios.

在 2020/8/4 下午10:16, Ilya Kasnacheev 写道:

Hello!

From the docs:

To avoid this situation with the swapping capabilities, you
need to :

  * Set |maxSize = bigger_ than_RAM_size|, in which case,
the OS will take care of the swapping.
  * Enable swapping by setting the
|DataRegionConfiguration.swapPath| property.


I actually think these are either-or. You should either do
the first (and configure OS swapping) or the second part.

Having said that, I recommend setting proper Native
Persistence instead.

Regards,
-- 
Ilya Kasnacheev



сб, 25 июл. 2020 г. в 04:49, 38797715 <38797...@qq.com
>:

Hi,

https://apacheignite.readme.io/docs/swap-space


According to the above document, if the physical memory
is small, you can solve this problem by opening the swap
space,The specific method is to configure maxSize to a
larger value (i.e. larger than the physical memory), and
the swapPath property needs to be configured.

But from the test results, the node is terminated.

I think the correct result should be that even if the
amount of data exceeds the physical memory, the node
should still be able to run normally, but the data is
exchanged to 

Re: Enabling swapPath causes invoking shutdown hook

[Denis Magda]

Ignite swapping is based on the swapping mechanism of the OS. So, you
shouldn’t see any difference if enable the OS one directly some way.

Generally, you should not use swapping of any form as a permanent
persistence layer due to the performance penalty. Once the swapping kicks
in, you should scale out your cluster and wait while the cluster rebalances
a part of the data to a new node. When the rebalancing completes, the
performance will be recovered and swapping won’t longer be needed.

Denis

On Thursday, August 13, 2020, 38797715 <38797...@qq.com> wrote:

> Hi,
>
> We retested and found that if we configured swapPath, as the amount of
> data increased, the write speed was actually slower and slower. If the
> amount of data is large, on average, it is much slower than the scenario
> where native persistence is enabled and wal is disabled.
>
> In this way, the use of the swapPath property has no productive value,
> maybe it was an early development function, and now it is a bit out of date.
>
> What I want to ask is, in the case of small physical memory, turning on
> persistence, and then configuring a larger maxSize (using the swap
> mechanism of the OS), is this a solution? In other words, the swap
> mechanism of the OS and the page replacement of Ignite, which is better?
> 在 2020/8/6 下午9:23, Ilya Kasnacheev 写道:
>
> Hello!
>
> I think the performance of swap space should be on par with persistence
> with disabled WAL.
>
> You can submit suggested updates to the documentation if you like.
>
> Regards,
> --
> Ilya Kasnacheev
>
>
> ср, 5 авг. 2020 г. в 06:00, 38797715 <38797...@qq.com>:
>
>> Hi Ilya,
>>
>> If so, there are two ways to implement ignite's swap space:
>> 1. maxSize > physical memory, which will use the swap mechanism of the
>> OS, can be used *vm.swappiness* Adjust.
>> 2. Configure the *swapPath* property, which is implemented by Ignite
>> itself, is independent of the OS and has no optimization parameters.
>> There's a choice between these two models, right? Then I think there may
>> be many problems in the description of the document. I hope you can check
>> it again:
>> https://apacheignite.readme.io/docs/swap-space
>>
>> After our initial testing, the performance of swap space is much better
>> than native persistence, so I think this pattern is valuable in some
>> scenarios.
>> 在 2020/8/4 下午10:16, Ilya Kasnacheev 写道:
>>
>> Hello!
>>
>> From the docs:
>>
>> To avoid this situation with the swapping capabilities, you need to :
>>
>>- Set maxSize = bigger_ than_RAM_size, in which case, the OS will
>>take care of the swapping.
>>- Enable swapping by setting the DataRegionConfiguration.swapPath
>> property.
>>
>>
>> I actually think these are either-or. You should either do the first (and
>> configure OS swapping) or the second part.
>>
>> Having said that, I recommend setting proper Native Persistence instead.
>>
>> Regards,
>> --
>> Ilya Kasnacheev
>>
>>
>> сб, 25 июл. 2020 г. в 04:49, 38797715 <38797...@qq.com>:
>>
>>> Hi,
>>>
>>> https://apacheignite.readme.io/docs/swap-space
>>>
>>> According to the above document, if the physical memory is small, you
>>> can solve this problem by opening the swap space,The specific method is to
>>> configure maxSize to a larger value (i.e. larger than the physical memory),
>>> and the swapPath property needs to be configured.
>>>
>>> But from the test results, the node is terminated.
>>>
>>> I think the correct result should be that even if the amount of data
>>> exceeds the physical memory, the node should still be able to run normally,
>>> but the data is exchanged to the disk.
>>>
>>> I want to know what parameters affect the behavior of this
>>> configuration? *vm.swappiness* or others?
>>> 在 2020/7/24 下午9:55, aealexsandrov 写道:
>>>
>>> Hi,
>>>
>>> Can you please clarify your expectations? You expected that JVM process will
>>> be killed instead of gracefully stopping? What you are going to achieve?
>>>
>>> BR,
>>> Andrei
>>>
>>>
>>>
>>> --
>>> Sent from: http://apache-ignite-users.70518.x6.nabble.com/
>>>
>>>

-- 
-
Denis

Re: Enabling swapPath causes invoking shutdown hook

[38797715]

Hi,

We retested and found that if we configured swapPath, as the amount of 
data increased, the write speed was actually slower and slower. If the 
amount of data is large, on average, it is much slower than the scenario 
where native persistence is enabled and wal is disabled.


In this way, the use of the swapPath property has no productive value, 
maybe it was an early development function, and now it is a bit out of date.


What I want to ask is, in the case of small physical memory, turning on 
persistence, and then configuring a larger maxSize (using the swap 
mechanism of the OS), is this a solution? In other words, the swap 
mechanism of the OS and the page replacement of Ignite, which is better?


在 2020/8/6 下午9:23, Ilya Kasnacheev 写道:

Hello!

I think the performance of swap space should be on par with 
persistence with disabled WAL.


You can submit suggested updates to the documentation if you like.

Regards,
--
Ilya Kasnacheev


ср, 5 авг. 2020 г. в 06:00, 38797715 <38797...@qq.com 
>:


Hi Ilya,

If so, there are two ways to implement ignite's swap space:
1. maxSize > physical memory, which will use the swap mechanism of
the OS, can be used *vm.swappiness* Adjust.
2. Configure the *swapPath* property, which is implemented by
Ignite itself, is independent of the OS and has no optimization
parameters.

There's a choice between these two models, right? Then I think
there may be many problems in the description of the document. I
hope you can check it again:
https://apacheignite.readme.io/docs/swap-space


After our initial testing, the performance of swap space is much
better than native persistence, so I think this pattern is
valuable in some scenarios.

在 2020/8/4 下午10:16, Ilya Kasnacheev 写道:

Hello!

From the docs:

To avoid this situation with the swapping capabilities, you need to :

  * Set |maxSize = bigger_ than_RAM_size|, in which case, the OS
will take care of the swapping.
  * Enable swapping by setting the
|DataRegionConfiguration.swapPath| property.


I actually think these are either-or. You should either do the
first (and configure OS swapping) or the second part.

Having said that, I recommend setting proper Native Persistence
instead.

Regards,
-- 
Ilya Kasnacheev



сб, 25 июл. 2020 г. в 04:49, 38797715 <38797...@qq.com
>:

Hi,

https://apacheignite.readme.io/docs/swap-space


According to the above document, if the physical memory is
small, you can solve this problem by opening the swap
space,The specific method is to configure maxSize to a larger
value (i.e. larger than the physical memory), and the
swapPath property needs to be configured.

But from the test results, the node is terminated.

I think the correct result should be that even if the amount
of data exceeds the physical memory, the node should still be
able to run normally, but the data is exchanged to the disk.

I want to know what parameters affect the behavior of this
configuration? *vm.swappiness* or others?

在 2020/7/24 下午9:55, aealexsandrov 写道:

Hi,

Can you please clarify your expectations? You expected that JVM process 
will
be killed instead of gracefully stopping? What you are going to achieve?

BR,
Andrei



--
Sent from:http://apache-ignite-users.70518.x6.nabble.com/  

Re: Enabling swapPath causes invoking shutdown hook

[Denis Magda]

Agree with Ilya that the performance should be comparable if you disable
the WAL of the Ignite persistence.

Anyway, the swapping and Ignite persistence pursue different goals. The
swapping is one of the out-of-memory protection techniques - if you run out
of DRAM, then the OS will start swapping in/out Ignite memory pages to
avoid a node outage. But, the swap space is not a durable storage layer. If
you restart the cluster, then all the swapped pages will evaporate. While,
Ignite persistence is your durable disk tier that survives cluster restarts
and, thus, uses more sophisticated algorithms to ensure data consistency
and durability. Just select what suits you best. I put more thoughts on
this in this article:
https://www.gridgain.com/resources/blog/out-of-memory-apache-ignite-cluster-handling-techniques

-
Denis


On Thu, Aug 6, 2020 at 6:23 AM Ilya Kasnacheev 
wrote:

> Hello!
>
> I think the performance of swap space should be on par with persistence
> with disabled WAL.
>
> You can submit suggested updates to the documentation if you like.
>
> Regards,
> --
> Ilya Kasnacheev
>
>
> ср, 5 авг. 2020 г. в 06:00, 38797715 <38797...@qq.com>:
>
>> Hi Ilya,
>>
>> If so, there are two ways to implement ignite's swap space:
>> 1. maxSize > physical memory, which will use the swap mechanism of the
>> OS, can be used *vm.swappiness* Adjust.
>> 2. Configure the *swapPath* property, which is implemented by Ignite
>> itself, is independent of the OS and has no optimization parameters.
>> There's a choice between these two models, right? Then I think there may
>> be many problems in the description of the document. I hope you can check
>> it again:
>> https://apacheignite.readme.io/docs/swap-space
>>
>> After our initial testing, the performance of swap space is much better
>> than native persistence, so I think this pattern is valuable in some
>> scenarios.
>> 在 2020/8/4 下午10:16, Ilya Kasnacheev 写道:
>>
>> Hello!
>>
>> From the docs:
>>
>> To avoid this situation with the swapping capabilities, you need to :
>>
>>- Set maxSize = bigger_ than_RAM_size, in which case, the OS will
>>take care of the swapping.
>>- Enable swapping by setting the DataRegionConfiguration.swapPath
>> property.
>>
>>
>> I actually think these are either-or. You should either do the first (and
>> configure OS swapping) or the second part.
>>
>> Having said that, I recommend setting proper Native Persistence instead.
>>
>> Regards,
>> --
>> Ilya Kasnacheev
>>
>>
>> сб, 25 июл. 2020 г. в 04:49, 38797715 <38797...@qq.com>:
>>
>>> Hi,
>>>
>>> https://apacheignite.readme.io/docs/swap-space
>>>
>>> According to the above document, if the physical memory is small, you
>>> can solve this problem by opening the swap space,The specific method is to
>>> configure maxSize to a larger value (i.e. larger than the physical memory),
>>> and the swapPath property needs to be configured.
>>>
>>> But from the test results, the node is terminated.
>>>
>>> I think the correct result should be that even if the amount of data
>>> exceeds the physical memory, the node should still be able to run normally,
>>> but the data is exchanged to the disk.
>>>
>>> I want to know what parameters affect the behavior of this
>>> configuration? *vm.swappiness* or others?
>>> 在 2020/7/24 下午9:55, aealexsandrov 写道:
>>>
>>> Hi,
>>>
>>> Can you please clarify your expectations? You expected that JVM process will
>>> be killed instead of gracefully stopping? What you are going to achieve?
>>>
>>> BR,
>>> Andrei
>>>
>>>
>>>
>>> --
>>> Sent from: http://apache-ignite-users.70518.x6.nabble.com/
>>>
>>>

Re: Enabling swapPath causes invoking shutdown hook

[Ilya Kasnacheev]

Hello!

I think the performance of swap space should be on par with persistence
with disabled WAL.

You can submit suggested updates to the documentation if you like.

Regards,
-- 
Ilya Kasnacheev


ср, 5 авг. 2020 г. в 06:00, 38797715 <38797...@qq.com>:

> Hi Ilya,
>
> If so, there are two ways to implement ignite's swap space:
> 1. maxSize > physical memory, which will use the swap mechanism of the OS,
> can be used *vm.swappiness* Adjust.
> 2. Configure the *swapPath* property, which is implemented by Ignite
> itself, is independent of the OS and has no optimization parameters.
> There's a choice between these two models, right? Then I think there may
> be many problems in the description of the document. I hope you can check
> it again:
> https://apacheignite.readme.io/docs/swap-space
>
> After our initial testing, the performance of swap space is much better
> than native persistence, so I think this pattern is valuable in some
> scenarios.
> 在 2020/8/4 下午10:16, Ilya Kasnacheev 写道:
>
> Hello!
>
> From the docs:
>
> To avoid this situation with the swapping capabilities, you need to :
>
>- Set maxSize = bigger_ than_RAM_size, in which case, the OS will take
>care of the swapping.
>- Enable swapping by setting the DataRegionConfiguration.swapPath
> property.
>
>
> I actually think these are either-or. You should either do the first (and
> configure OS swapping) or the second part.
>
> Having said that, I recommend setting proper Native Persistence instead.
>
> Regards,
> --
> Ilya Kasnacheev
>
>
> сб, 25 июл. 2020 г. в 04:49, 38797715 <38797...@qq.com>:
>
>> Hi,
>>
>> https://apacheignite.readme.io/docs/swap-space
>>
>> According to the above document, if the physical memory is small, you can
>> solve this problem by opening the swap space,The specific method is to
>> configure maxSize to a larger value (i.e. larger than the physical memory),
>> and the swapPath property needs to be configured.
>>
>> But from the test results, the node is terminated.
>>
>> I think the correct result should be that even if the amount of data
>> exceeds the physical memory, the node should still be able to run normally,
>> but the data is exchanged to the disk.
>>
>> I want to know what parameters affect the behavior of this configuration?
>> *vm.swappiness* or others?
>> 在 2020/7/24 下午9:55, aealexsandrov 写道:
>>
>> Hi,
>>
>> Can you please clarify your expectations? You expected that JVM process will
>> be killed instead of gracefully stopping? What you are going to achieve?
>>
>> BR,
>> Andrei
>>
>>
>>
>> --
>> Sent from: http://apache-ignite-users.70518.x6.nabble.com/
>>
>>

Re: Enabling swapPath causes invoking shutdown hook

[38797715]

Hi Ilya,

If so, there are two ways to implement ignite's swap space:
1. maxSize > physical memory, which will use the swap mechanism of the 
OS, can be used *vm.swappiness* Adjust.
2. Configure the *swapPath* property, which is implemented by Ignite 
itself, is independent of the OS and has no optimization parameters.


There's a choice between these two models, right? Then I think there may 
be many problems in the description of the document. I hope you can 
check it again:

https://apacheignite.readme.io/docs/swap-space

After our initial testing, the performance of swap space is much better 
than native persistence, so I think this pattern is valuable in some 
scenarios.


在 2020/8/4 下午10:16, Ilya Kasnacheev 写道:

Hello!

From the docs:

To avoid this situation with the swapping capabilities, you need to :

  * Set |maxSize = bigger_ than_RAM_size|, in which case, the OS will
take care of the swapping.
  * Enable swapping by setting the
|DataRegionConfiguration.swapPath| property.


I actually think these are either-or. You should either do the first 
(and configure OS swapping) or the second part.


Having said that, I recommend setting proper Native Persistence instead.

Regards,
--
Ilya Kasnacheev


сб, 25 июл. 2020 г. в 04:49, 38797715 <38797...@qq.com 
>:


Hi,

https://apacheignite.readme.io/docs/swap-space


According to the above document, if the physical memory is small,
you can solve this problem by opening the swap space,The specific
method is to configure maxSize to a larger value (i.e. larger than
the physical memory), and the swapPath property needs to be
configured.

But from the test results, the node is terminated.

I think the correct result should be that even if the amount of
data exceeds the physical memory, the node should still be able to
run normally, but the data is exchanged to the disk.

I want to know what parameters affect the behavior of this
configuration? *vm.swappiness* or others?

在 2020/7/24 下午9:55, aealexsandrov 写道:

Hi,

Can you please clarify your expectations? You expected that JVM process will
be killed instead of gracefully stopping? What you are going to achieve?

BR,
Andrei



--
Sent from:http://apache-ignite-users.70518.x6.nabble.com/  

Re: Enabling swapPath causes invoking shutdown hook

[Ilya Kasnacheev]

Hello!

>From the docs:

To avoid this situation with the swapping capabilities, you need to :

   - Set maxSize = bigger_ than_RAM_size, in which case, the OS will take
   care of the swapping.
   - Enable swapping by setting the DataRegionConfiguration.swapPath
property.


I actually think these are either-or. You should either do the first (and
configure OS swapping) or the second part.

Having said that, I recommend setting proper Native Persistence instead.

Regards,
-- 
Ilya Kasnacheev


сб, 25 июл. 2020 г. в 04:49, 38797715 <38797...@qq.com>:

> Hi,
>
> https://apacheignite.readme.io/docs/swap-space
>
> According to the above document, if the physical memory is small, you can
> solve this problem by opening the swap space,The specific method is to
> configure maxSize to a larger value (i.e. larger than the physical memory),
> and the swapPath property needs to be configured.
>
> But from the test results, the node is terminated.
>
> I think the correct result should be that even if the amount of data
> exceeds the physical memory, the node should still be able to run normally,
> but the data is exchanged to the disk.
>
> I want to know what parameters affect the behavior of this configuration?
> *vm.swappiness* or others?
> 在 2020/7/24 下午9:55, aealexsandrov 写道:
>
> Hi,
>
> Can you please clarify your expectations? You expected that JVM process will
> be killed instead of gracefully stopping? What you are going to achieve?
>
> BR,
> Andrei
>
>
>
> --
> Sent from: http://apache-ignite-users.70518.x6.nabble.com/
>
>

Re: Enabling swapPath causes invoking shutdown hook

[aealexsandrov]

Hi,

Documentation looks not very clean for me. Probably you should prepare your
operating system to use swap space. Can you try to prepare the swap file
first as following:

https://linuxize.com/post/how-to-add-swap-space-on-ubuntu-18-04/

And then choose this file. 

BR,
Andrei



--
Sent from: http://apache-ignite-users.70518.x6.nabble.com/

Re: Enabling swapPath causes invoking shutdown hook

[38797715]

Hi,

https://apacheignite.readme.io/docs/swap-space

According to the above document, if the physical memory is small, you 
can solve this problem by opening the swap space,The specific method is 
to configure maxSize to a larger value (i.e. larger than the physical 
memory), and the swapPath property needs to be configured.


But from the test results, the node is terminated.

I think the correct result should be that even if the amount of data 
exceeds the physical memory, the node should still be able to run 
normally, but the data is exchanged to the disk.


I want to know what parameters affect the behavior of this 
configuration? *vm.swappiness* or others?


在 2020/7/24 下午9:55, aealexsandrov 写道:

Hi,

Can you please clarify your expectations? You expected that JVM process will
be killed instead of gracefully stopping? What you are going to achieve?

BR,
Andrei



--
Sent from: http://apache-ignite-users.70518.x6.nabble.com/

Re: Enabling swapPath causes invoking shutdown hook

[aealexsandrov]

Hi,

Can you please clarify your expectations? You expected that JVM process will
be killed instead of gracefully stopping? What you are going to achieve?

BR,
Andrei



--
Sent from: http://apache-ignite-users.70518.x6.nabble.com/

Enabling swapPath causes invoking shutdown hook

[38797715]

Hi community,

When swapPath is configured in DataRegionConfiguration and maxSize is 
greater than the physical memory (that is, swap space is enabled), if 
the amount of data exceeds the physical memory, a node failure will 
occur. The log is as follows:


[08:29:14,212][INFO][Thread-24][G] Invoking shutdown hook...

I think the node process may be killed by the OS. What parameters can be 
adjusted?