Hi, Slava!
Thank you for looking at the offer and making fair comments.
I personally discussed with Anton and Alexey because they are author and
sponsor of "IEP-40" and we found out that point 2 in it is no longer relevant
and it can be removed.
I suggest implementing point 3, since it may be independent of point 1. Also,
the warm-up will always start after restore phase, without subscribing to
events.
You are right this should be mentioned in the documentation and javadoc.
> This means that the user's thread, which starts Ignite via
> Ignition.start(), will wait for ana additional step - cache warm-up.
> I think this fact has to be clearly mentioned in our documentation (at
> Javadocat least) because this step can be time-consuming.
My suggestion for implementation:
1)Adding a marker interface
"org.apache.ignite.configuration.WarmUpConfiguration" for configuring cache
warming;
2)Set only one configuration via
"org.apache.ignite.configuration.IgniteConfiguration#setWarmUpConfiguration";
3)Add an internal warm-up interface that will start in [1] after [2];
package org.apache.ignite.internal.processors.cache.warmup;
import org.apache.ignite.IgniteCheckedException;
import org.apache.ignite.configuration.WarmUpConfiguration;
import org.apache.ignite.internal.GridKernalContext;
/**
* Interface for warming up.
*/
public interface WarmUpStrategy<T extends WarmUpConfiguration> {
/**
* Returns configuration class for mapping to strategy.
*
* @return Configuration class.
*/
Class<T> configClass();
/**
* Warm up.
*
* @param kernalCtx Kernal context.
* @param cfg Warm-up configuration.
* @throws IgniteCheckedException if faild.
*/
void warmUp(GridKernalContext kernalCtx, T cfg) throws
IgniteCheckedException;
}
4)Adding an internal plugin extension for add own strategies;
package org.apache.ignite.internal.processors.cache.warmup;
import java.util.Collection;
import org.apache.ignite.plugin.Extension;
/**
* Interface for getting warm-up strategies from plugins.
*/
public interface WarmUpStrategySupplier extends Extension {
/**
* Getting warm-up strategies.
*
* @return Warm-up strategies.
*/
Collection<WarmUpStrategy> strategies();
}
5)Add a "Load all" strategy that will load everything to memory as long as
there is space in it. This strategy is suitable if the persistent storage is
less than RAM.
Any objections or comments?
[1] -
org.apache.ignite.internal.processors.cache.GridCacheProcessor.CacheRecoveryLifecycle#afterLogicalUpdatesApplied
[2] -
org.apache.ignite.internal.processors.cache.GridCacheProcessor.CacheRecoveryLifecycle#restorePartitionStates
27.07.2020, 16:48, "Вячеслав Коптилин" <slava.kopti...@gmail.com>:
> Hello Kirill,
>
> Thanks a lot for driving this activity. If I am not mistaken, this
> discussion relates to IEP-40.
>
>> I suggest adding a warmup phase after recovery here [1] after [2], before
>
> discovery.
> This means that the user's thread, which starts Ignite via
> Ignition.start(), will wait for ana additional step - cache warm-up.
> I think this fact has to be clearly mentioned in our documentation (at
> Javadocat least) because this step can be time-consuming.
>
>> I suggest adding a new interface:
>
> I would change it a bit. First of all, it would be nice to place this
> interface to a public package and get rid of using GridCacheContext,
> which is an internal class and it should not leak to the public API in any
> case.
> Perhaps, this parameter is not needed at all or we should add some public
> abstraction instead of internal class.
>
> package org.apache.ignite.configuration;
>
> import org.apache.ignite.IgniteCheckedException;
> import org.apache.ignite.lang.IgniteFuture;
>
> public interface CacheWarmupper {
> /**
> * Warmup cache.
> *
> * @param cachename Cache name.
> * @return Future cache warmup.
> * @throws IgniteCheckedException If failed.
> */
> IgniteFuture<?> warmup(String cachename) throws IgniteCheckedException;
> }
>
> Thanks,
> S.
>
> пн, 27 июл. 2020 г. в 15:03, ткаленко кирилл <tkalkir...@yandex.ru>:
>
>> Now, after restarting node, we have only cold caches, which at first
>> requests to them will gradually load data from disks, which can slow down
>> first calls to them.
>> If node has more RAM than data on disk, then they can be loaded at start
>> "warmup", thereby solving the issue of slowdowns during first calls to
>> caches.
>>
>> I suggest adding a warmup phase after recovery here [1] after [2], before
>> descovery.
>>
>> I suggest adding a new interface:
>>
>> package org.apache.ignite.internal.processors.cache;
>>
>> import org.apache.ignite.IgniteCheckedException;
>> import org.apache.ignite.internal.IgniteInternalFuture;
>> import org.jetbrains.annotations.Nullable;
>>
>> /**
>> * Interface for warming up cache.
>> */
>> public interface CacheWarmup {
>> /**
>> * Warmup cache.
>> *
>> * @param cacheCtx Cache context.
>> * @return Future cache warmup.
>> * @throws IgniteCheckedException if failed.
>> */
>> @Nullable IgniteInternalFuture<?> process(GridCacheContext cacheCtx)
>> throws IgniteCheckedException;
>> }
>>
>> Which will allow to warm up caches in parallel and asynchronously. Warmup
>> phase will end after all IgniteInternalFuture for all caches isDone.
>>
>> Also adding the ability to customize via methods:
>> org.apache.ignite.configuration.IgniteConfiguration#setDefaultCacheWarmup
>> org.apache.ignite.configuration.CacheConfiguration#setCacheWarmup
>>
>> Which will allow for each cache to set implementation of cache warming up,
>> both for a specific cache, and for all if necessary.
>>
>> I suggest adding an implementation of SequentialWarmup that will use [3].
>>
>> Questions, suggestions, comments?
>>
>> [1] -
>>
>> org.apache.ignite.internal.processors.cache.GridCacheProcessor.CacheRecoveryLifecycle#afterLogicalUpdatesApplied
>> [2] -
>>
>> org.apache.ignite.internal.processors.cache.GridCacheProcessor.CacheRecoveryLifecycle#restorePartitionStates
>> [3] -
>>
>> org.apache.ignite.internal.processors.cache.IgniteCacheOffheapManager.CacheDataStore#preload
