Hi, Ignite CacheConfiguration inherits setWriteThrough method from JCache API [1]. Enabled writeThrough in JCache means that cache is backed by some other storage to which writes are propagated along with writes to to the cache. Unfortunately (or not?) JCache uses write-through term while Ignite supports write-behind write propagation policy. Perhaps API is not clear enough but I think that JCache conformance is the clue here.
[1] https://static.javadoc.io/javax.cache/cache-api/1.1.0/javax/cache/configuration/MutableConfiguration.html#setWriteThrough-boolean- вт, 5 мар. 2019 г. в 16:59, relax ken <relax....@gmail.com>: > > Thanks Ilya. I guess conceptually there are many explanations and definitions > about those two on Internet which may agree, disagree, or consensus on some > point. My question is more about their impact when they are true or false in > Ignite. > > For example, if it's always the case, why doesn't Ignite just encapsulate > this kind assumption, take care it and auto set write through true while > write behind is set to true. Why does Ignite give this kind of option and > warning? Will there be any difference when write behind is true but write > through is not true? try to understand deeper about those options to avoid > any unexpected behaviour. > > On Tue, Mar 5, 2019 at 1:46 PM Ilya Kasnacheev <ilya.kasnach...@gmail.com> > wrote: >> >> Hello! >> >> It is because write-behing is a kind of write-through. Like random access >> memory is a kind of computer memory. >> >> Regards, >> -- >> Ilya Kasnacheev >> >> >> вт, 5 мар. 2019 г. в 14:43, relax ken <relax....@gmail.com>: >>> >>> Hi, >>> >>> I am new to Ignite. When I enable write behind, I always get a warning >>> "Write-behind mode for the cache store also requires >>> CacheConfiguration.setWriteThrough(true) property." Why does write behind >>> require write through when I am using write behind only? >>> >>> Here is my configuration >>> >>> CacheConfiguration<String, Document> cconfig = new CacheConfiguration<>(); >>> cconfig.setAtomicityMode(CacheAtomicityMode.ATOMIC); >>> cconfig.setCacheMode(CacheMode.PARTITIONED); >>> cconfig.setName(Constants.DocCacheName); >>> cconfig.setExpiryPolicyFactory(TouchedExpiryPolicy.factoryOf(new >>> Duration(TimeUnit.SECONDS, cacheConfig.cacheExpirySecs))); >>> >>> cconfig.setWriteBehindEnabled(true); >>> cconfig.setWriteBehindFlushFrequency(cacheConfig.writeBehindFlushIntervalSec); >>> // MS >>> >>> >>> Thanks >>> >>> Ken -- Best regards, Ivan Pavlukhin
