My variant of API avoids cache configuration. One more thing to note - as we found out control.sh cannot dump XML configuration. Currently it returns only subset of properties. And in general case it is impossible to convert CacheConfiguration to Spring XML, because Spring XMLis not serialization protocol. So API with CacheConfiguration doesn’t seem to work for control.sh as well.
чт, 22 нояб. 2018 г. в 10:05, Eduard Shangareev <eduard.shangar...@gmail.com >: > Vovan, > > We couldn't avoid API with cache configuration. > Almost all of ~70 properties could be changed, some of them are instances > of objects or could be user-defined class. > Could you come up with alternatives for user-defined affinity function? > > Also, the race would have a place in other scenarios. > > > > On Thu, Nov 22, 2018 at 8:50 AM Vladimir Ozerov <voze...@gridgain.com> > wrote: > > > Ed, > > > > We may have API similar to “cache” and “getOrCreateCache”, or may not. It > > is up to us to decide. Similarity on it’s own is weak argument. > > Functionality and simplicity - this is what matters. > > > > Approach with cache configuration has three major issues > > 1) It exposes properties which user will not be able to change, so > typical > > user actions would be: try to change property, fail as it is unsupported, > > go reading documentation. Approach with separate POJO is intuitive and > > self-documenting. > > 2) It has race condition between config read and config apply, so user do > > not know what exactly he changes, unless you change API to something like > > “restartCaches(Tuple<CacheConfiguration, CacheConfiguration>...)”, which > > user will need to call in a loop. > > 3) And it is not suitable for non-Java platform, which is a showstopper - > > all API should be available from all platforms unless it is proven to be > > impossible to implement. > > > > Vladimir. > > > > чт, 22 нояб. 2018 г. в 1:06, Eduard Shangareev < > > eduard.shangar...@gmail.com > > >: > > > > > Vovan, > > > > > > Would you argue that we should have the similar API in Java as > > > Ignite.cache(CacheConfiguration) or > > > Ignite.getOrCreateCache(CacheConfiguration)? > > > > > > With a proposed solution, every other API call would rely on it > finally. > > > > > > I am interested in having such feature not arguing about API > > alternatives. > > > > > > We definitely should have the ability to change it via control.sh and > > Java > > > API. Everything else is optional from my point of view (at least on the > > > current stage). > > > > > > Moreover, your arguments are more about our format of > CacheConfiguration > > > which couldn't be defined in other languages and clients. So, maybe we > > > should start a discussion about how we should change it in 3.0? > > > > > > > > > > > > > > > On Wed, Nov 21, 2018 at 7:45 PM Vladimir Ozerov <voze...@gridgain.com> > > > wrote: > > > > > > > Ed, > > > > > > > > Why do we want to operate on CacheConfiguration so desperately? Your > > > > example raises even more questions: > > > > 1) What to do with thin clients? > > > > 2) What to do with aforementioned race conditions, when cache could > be > > > > changed concurrently? > > > > 3) Why such trivial operation from user perspective is only supported > > > from > > > > control.sh and not from the rest API (even Java client nodes will be > > > > affected - remember our plans to remove requirement to have cache > > classes > > > > on client nodes, which is yet to be implemented). > > > > > > > > Compare it to alternative API: > > > > > > > > 1) Native call from any language without limitations: > > > > > > > > > > > > > > Ignite.changeCache(CacheConfigurationChange.create().setCacheMode(REPLICATED).setBackups(2)); > > > > > > > > 2) Call from control.sh in one line without race conditions with > > > concurrent > > > > cache changes: > > > > control.sh --cache --change cacheMode=REPLICATED backups=2 > > > > > > > > On Wed, Nov 21, 2018 at 7:32 PM Eduard Shangareev < > > > > eduard.shangar...@gmail.com> wrote: > > > > > > > > > Vovan, > > > > > > > > > > user already is able to get cache configuration as xml. > > > > > control.sh --cache list '.' --config > > > > > > > > > > So, user could update it and run: > > > > > control.sh --cache --restart -cfg=xml.path > > > > > > > > > > > > > > > On Wed, Nov 21, 2018 at 7:06 PM Vladimir Ozerov < > > voze...@gridgain.com> > > > > > wrote: > > > > > > > > > > > Ed, > > > > > > > > > > > > He can do that programmatically. But I meant another case - Java > > node > > > > > > creates a cache. Then .NET node wants to change it. Proposed API > > > cannot > > > > > > handle it. > > > > > > > > > > > > ср, 21 нояб. 2018 г. в 19:03, Eduard Shangareev < > > > > > eshangar...@gridgain.com > > > > > > >: > > > > > > > > > > > > > Vladimir, > > > > > > > > > > > > > > I didn't get how does .Net user start caches right now? XML and > > > > remote > > > > > > > node? Right? > > > > > > > > > > > > > > > > > > > > > On Wed, Nov 21, 2018 at 6:55 PM Vladimir Ozerov < > > > > voze...@gridgain.com> > > > > > > > wrote: > > > > > > > > > > > > > > > Ed, > > > > > > > > > > > > > > > > We are not Java product. We support 6 platforms at the > moment. > > > Why > > > > do > > > > > > we > > > > > > > > implement a feature which can only be used in Java, when it > is > > > very > > > > > > easy > > > > > > > to > > > > > > > > make it available from everywhere? > > > > > > > > > > > > > > > > ср, 21 нояб. 2018 г. в 18:50, Eduard Shangareev < > > > > > > > eshangar...@gridgain.com > > > > > > > > >: > > > > > > > > > > > > > > > > > Vladimir, > > > > > > > > > > > > > > > > > > It would be Java API specific. > > > > > > > > > For a user, we would add a new command for console.sh which > > > would > > > > > > take > > > > > > > an > > > > > > > > > XML-file path as a parameter. > > > > > > > > > > > > > > > > > > We could add other possibilities: for example, with the > > builder > > > > > which > > > > > > > > would > > > > > > > > > finally call this Ignite.restartCaches method. But it's > nice > > to > > > > > have, > > > > > > > > not a > > > > > > > > > mandatory one. > > > > > > > > > > > > > > > > > > On Wed, Nov 21, 2018 at 6:43 PM Vladimir Ozerov < > > > > > > voze...@gridgain.com> > > > > > > > > > wrote: > > > > > > > > > > > > > > > > > > > Ed, > > > > > > > > > > > > > > > > > > > > Could you please demonstrate how .NET node or .NET will > > > change > > > > > > cache > > > > > > > > > > configuration with proposed API? Taking in count that XML > > is > > > > not > > > > > > > > > available > > > > > > > > > > in most cases, and custom Java classes from cache > > > configuration > > > > > are > > > > > > > > > > available only on server nodes and only from Java. > > > > > > > > > > > > > > > > > > > > ср, 21 нояб. 2018 г. в 18:36, Eduard Shangareev < > > > > > > > > > > eduard.shangar...@gmail.com > > > > > > > > > > >: > > > > > > > > > > > > > > > > > > > > > Vladimir, > > > > > > > > > > > > > > > > > > > > > > I don't see any difference here. > > > > > > > > > > > > > > > > > > > > > > The same possibilities would be available as with > normal > > > > cache > > > > > > > start: > > > > > > > > > > > -XML; > > > > > > > > > > > -remote node. > > > > > > > > > > > > > > > > > > > > > > >3) Avoid race condition when configuration changes > > between > > > > > > > > > configuration > > > > > > > > > > > read and method call (what could lead to a number of > > > strange > > > > > > > > effects). > > > > > > > > > > > > > > > > > > > > > > Well, we could add *old* configuration parameter for > > > CAS-like > > > > > > > > semantic. > > > > > > > > > > > > > > > > > > > > > > On Wed, Nov 21, 2018 at 6:26 PM Vladimir Ozerov < > > > > > > > > voze...@gridgain.com> > > > > > > > > > > > wrote: > > > > > > > > > > > > > > > > > > > > > > > Ed, > > > > > > > > > > > > > > > > > > > > > > > > Caches in .NET could be started programmatically, > from > > > XML > > > > > > which > > > > > > > > .NET > > > > > > > > > > API > > > > > > > > > > > > has no access to, or dynamically from remote nodes > (eg > > > Java > > > > > > > node). > > > > > > > > > > > > > > > > > > > > > > > > ср, 21 нояб. 2018 г. в 18:24, Eduard Shangareev < > > > > > > > > > > > > eduard.shangar...@gmail.com > > > > > > > > > > > > >: > > > > > > > > > > > > > > > > > > > > > > > > > Vladimir, > > > > > > > > > > > > > > > > > > > > > > > > > > How does .Net user start caches right now? > > > > > > > > > > > > > > > > > > > > > > > > > > On Wed, Nov 21, 2018 at 6:10 PM Vladimir Ozerov < > > > > > > > > > > voze...@gridgain.com> > > > > > > > > > > > > > wrote: > > > > > > > > > > > > > > > > > > > > > > > > > > > Eduard, > > > > > > > > > > > > > > > > > > > > > > > > > > > > Simple != correct. Let’s consider a simple use > > case: > > > > user > > > > > > > want > > > > > > > > to > > > > > > > > > > > > change > > > > > > > > > > > > > > PARTITIONED -> REPLICATED from .NET, but do not > > some > > > > > > classes > > > > > > > > from > > > > > > > > > > > > > > CacheConfiguration. How do we solve this? > > > > > > > > > > > > > > > > > > > > > > > > > > > > Vladimir. > > > > > > > > > > > > > > > > > > > > > > > > > > > > ср, 21 нояб. 2018 г. в 18:02, Eduard Shangareev < > > > > > > > > > > > > > > eduard.shangar...@gmail.com > > > > > > > > > > > > > > >: > > > > > > > > > > > > > > > > > > > > > > > > > > > > > Vladimir, > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > I propose not to change cache configuration in > > > > runtime > > > > > > but > > > > > > > > > > restart > > > > > > > > > > > > > cache > > > > > > > > > > > > > > > with the new compatible configuration on data > > which > > > > we > > > > > > have > > > > > > > > > > > > underfoot. > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > What we could change: > > > > > > > > > > > > > > > -backup count; > > > > > > > > > > > > > > > -TRANSACTIONAL <-> ATOMIC; > > > > > > > > > > > > > > > -REPLICATED - PARTITIONED; > > > > > > > > > > > > > > > -other settings. > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > So, yeah, it would be great to have a > possibility > > > to > > > > > > change > > > > > > > > > some > > > > > > > > > > > > > > properties > > > > > > > > > > > > > > > in runtime. But right we don't any way to > change > > > > > anything > > > > > > > > > except > > > > > > > > > > > > > indexes > > > > > > > > > > > > > > > and SQL fields. > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > We already have all mechanism to do this. > > > > > > > > > > > > > > > The main issue is to make it reliable and > exclude > > > > cases > > > > > > > when > > > > > > > > we > > > > > > > > > > > could > > > > > > > > > > > > > > come > > > > > > > > > > > > > > > to the unrecoverable state. > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > So, I suggest keeping the solution as simple as > > > > > possible. > > > > > > > > > > > > > > > For indexes clashes and ClassNotFoundException > we > > > > could > > > > > > > > revert > > > > > > > > > > > > > > > configuration update and start with the old > > > > > > configuration. > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > On Wed, Nov 21, 2018 at 5:44 PM Vladimir > Ozerov < > > > > > > > > > > > > voze...@gridgain.com> > > > > > > > > > > > > > > > wrote: > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > Eduard, > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > Got it. Please take the following things in > > count > > > > > > during > > > > > > > > > > design: > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > 1) Two distinct PMEs might not work well. > > > Consider > > > > a > > > > > > > > > situation > > > > > > > > > > > > w1hen > > > > > > > > > > > > > I > > > > > > > > > > > > > > > > decided to move a cache with index "MY_INDEX" > > > from > > > > > > > schema A > > > > > > > > > to > > > > > > > > > > > > schema > > > > > > > > > > > > > > B. > > > > > > > > > > > > > > > > While cache was stopped, another cache with > > index > > > > > > > > "MY_INDEX" > > > > > > > > > > was > > > > > > > > > > > > > > created > > > > > > > > > > > > > > > in > > > > > > > > > > > > > > > > schema B. Now first cache cannot start due to > > > index > > > > > > name > > > > > > > > > > > conflict. > > > > > > > > > > > > > > > > 2) Cancelling index creation is also bad idea > > > > because > > > > > > > this > > > > > > > > is > > > > > > > > > > > > > > potentially > > > > > > > > > > > > > > > > long operation. Instead, most likely that we > > > should > > > > > > wait > > > > > > > to > > > > > > > > > > > > > concurrent > > > > > > > > > > > > > > > > schema operations to finish first. That is, > all > > > > > > > operations > > > > > > > > on > > > > > > > > > > > cache > > > > > > > > > > > > > > > should > > > > > > > > > > > > > > > > be ordered wrt each other somehow > > > > > > > > > > > > > > > > 3) Why do we think that cache restart will be > > > > needed > > > > > at > > > > > > > > all? > > > > > > > > > We > > > > > > > > > > > > have > > > > > > > > > > > > > a > > > > > > > > > > > > > > > lot > > > > > > > > > > > > > > > > of configuration properties which could be > > > changed > > > > > > safely > > > > > > > > > > either > > > > > > > > > > > > > > without > > > > > > > > > > > > > > > > PME or with a single PME. - rebalance > > properties, > > > > > cache > > > > > > > > store > > > > > > > > > > > > > > properties > > > > > > > > > > > > > > > > (especially write-behind stuff), some query > > > > > properties > > > > > > > > (e.g. > > > > > > > > > > > > "detail > > > > > > > > > > > > > > > > metrics"), etc.. In essence, it seems that > >50% > > > of > > > > > > > > properties > > > > > > > > > > > could > > > > > > > > > > > > > be > > > > > > > > > > > > > > > > changed without cache restart, other 25% will > > not > > > > be > > > > > > > > > supported, > > > > > > > > > > > and > > > > > > > > > > > > > the > > > > > > > > > > > > > > > > rest may require restart. > > > > > > > > > > > > > > > > 4) Client nodes and thin client may not have > > > > > necessary > > > > > > > > > classes > > > > > > > > > > in > > > > > > > > > > > > > > > > classpath. E.g. consider a user which want to > > > > change > > > > > > > > > rebalance > > > > > > > > > > > > > timeout > > > > > > > > > > > > > > > for > > > > > > > > > > > > > > > > cache, but do not have configured interceptor > > in > > > > > > > classpath. > > > > > > > > > > With > > > > > > > > > > > > > > proposed > > > > > > > > > > > > > > > > API it will be impossible. This is especially > > > true > > > > > for > > > > > > > > > non-Java > > > > > > > > > > > > > > clients. > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > That said, I think we should consider another > > API > > > > > which > > > > > > > > will > > > > > > > > > > not > > > > > > > > > > > > > > require > > > > > > > > > > > > > > > > full CacheConfiguration object. This might > be a > > > > kind > > > > > of > > > > > > > > > builder > > > > > > > > > > > or > > > > > > > > > > > > > so. > > > > > > > > > > > > > > > And > > > > > > > > > > > > > > > > once user set properties he want to change to > > the > > > > > > > builder, > > > > > > > > we > > > > > > > > > > can > > > > > > > > > > > > > > analyze > > > > > > > > > > > > > > > > them and either change them in runtime > without > > > PME, > > > > > > > change > > > > > > > > > > with a > > > > > > > > > > > > > > single > > > > > > > > > > > > > > > > PME or change with full cache restart. > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > What do you think? > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > Vladimir. > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > On Wed, Nov 21, 2018 at 5:01 PM Eduard > > > Shangareev < > > > > > > > > > > > > > > > > eshangar...@gridgain.com> > > > > > > > > > > > > > > > > wrote: > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > Vladimir, > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > 1) Affinity could be changed, but count of > > > > > partition > > > > > > > > > couldn't > > > > > > > > > > > be. > > > > > > > > > > > > > > > > > 2) So it would trigger 2 PME. Dynamic start > > and > > > > > stop. > > > > > > > > > > > > > > > > > 3) In theory, should cancel them and new > > > setting > > > > > > should > > > > > > > > be > > > > > > > > > > > > applied. > > > > > > > > > > > > > > How > > > > > > > > > > > > > > > > it > > > > > > > > > > > > > > > > > works now? Create an index and stop node, > for > > > > > > example. > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > On Wed, Nov 21, 2018 at 4:56 PM Vladimir > > > Ozerov < > > > > > > > > > > > > > > voze...@gridgain.com> > > > > > > > > > > > > > > > > > wrote: > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > Hi Ed, > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > Several questions from my side: > > > > > > > > > > > > > > > > > > 1) If we do not allow to change the most > > > > demanded > > > > > > by > > > > > > > > > users > > > > > > > > > > > > things > > > > > > > > > > > > > > > like > > > > > > > > > > > > > > > > > > affinity or persistence/in-memory, then > > what > > > > kind > > > > > > of > > > > > > > > > > > > > configuration > > > > > > > > > > > > > > > > > > properties do we expect to be changed? > Can > > we > > > > > have > > > > > > > > > several > > > > > > > > > > > > > > examples? > > > > > > > > > > > > > > > > > > 2) How will it interact with PME? > > > > > > > > > > > > > > > > > > 3) How will it interact with CREATE INDEX > > and > > > > > ALTER > > > > > > > > TABLE > > > > > > > > > > > > > commands? > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > On Wed, Nov 21, 2018 at 4:48 PM Eduard > > > > > Shangareev < > > > > > > > > > > > > > > > > > > eduard.shangar...@gmail.com> wrote: > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > Igniters, > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > I propose new public API to change the > > > cache > > > > > > > > > > configuration > > > > > > > > > > > of > > > > > > > > > > > > > > > > > persistent > > > > > > > > > > > > > > > > > > > caches with keeping data. > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > It would look like: > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > Ignite ignite = ...; > > > > > > > > > > > > > > > > > > > ignite.restartCaches(cfg1, ... cfgN); > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > where cfgX is a new cache > configuration, > > > > which > > > > > > > > contains > > > > > > > > > > the > > > > > > > > > > > > > name > > > > > > > > > > > > > > of > > > > > > > > > > > > > > > > an > > > > > > > > > > > > > > > > > > > existing persistent cache. > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > The obvious limitation: > > > > > > > > > > > > > > > > > > > - affinity key mapping couldn't be > > changed; > > > > > > > > > > > > > > > > > > > - count of partitions couldn't be > > changed; > > > > > > > > > > > > > > > > > > > - MVCC couldn't be turned off/on; > > > > > > > > > > > > > > > > > > > - persistent couldn't be turned off; > > > > > > > > > > > > > > > > > > > - group settings couldn't be changed > > (group > > > > > > name); > > > > > > > > > > > > > > > > > > > - if cache belongs to group it's needed > > to > > > > > > restart > > > > > > > > all > > > > > > > > > of > > > > > > > > > > > > them. > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > Failure scenario is the crucial thing > > (and > > > > most > > > > > > > > > > difficult): > > > > > > > > > > > > > > > > > > > - initiator fail; > > > > > > > > > > > > > > > > > > > - cluster restart at any stage; > > > > > > > > > > > > > > > > > > > - joining/starting offline nodes. > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > Some thoughts about implementation: > > > > > > > > > > > > > > > > > > > - stop cache with destroy=false; > > > > > > > > > > > > > > > > > > > - start cache dynamically with new > > > > > configuration; > > > > > > > > > > > > > > > > > > > - if indexes settings changed - remove > > > > > index.bin > > > > > > to > > > > > > > > > start > > > > > > > > > > > > > > > indexation; > > > > > > > > > > > > > > > > > > > - change blt-history when start cache > > > > initiated > > > > > > to > > > > > > > > not > > > > > > > > > > > allow > > > > > > > > > > > > > join > > > > > > > > > > > > > > > > nodes > > > > > > > > > > > > > > > > > > > with old configuration; > > > > > > > > > > > > > > > > > > > - use restartId (IGNITE-8911) to not > > allow > > > to > > > > > > start > > > > > > > > > cache > > > > > > > > > > > in > > > > > > > > > > > > > > > between. > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > Your thoughts? Would it be a useful > > > feature? > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > -- > > > > > > > > > > > > > > > > > Best regards, > > > > > > > > > > > > > > > > > Eduard. > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > -- > > > > > > > > > Best regards, > > > > > > > > > Eduard. > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > -- > > > > > > > Best regards, > > > > > > > Eduard. > > > > > > > > > > > > > > > > > > > > > > > > > > > >
