The problem is with the same query as phrase. q="network se*". The last . is fullstops for the sentence and the query is q=field:"network se*"
Best, Modassar On Mon, Nov 2, 2015 at 6:10 PM, jim ferenczi <jim.feren...@gmail.com> wrote: > Oups I did not read the thread carrefully. > *The problem is with the same query as phrase. q="network se*".* > I was not aware that you could do that with Solr ;). I would say this is > expected because in such case if the number of expansions for "se*" is big > then you would have to check the positions for a significant words. I don't > know if there is a limitation in the number of expansions for a prefix > query contained into a phrase query but I would look at this parameter > first (limit the number of expansion per prefix search, let's say the N > most significant words based on the frequency of the words for instance). > > 2015-11-02 13:36 GMT+01:00 jim ferenczi <jim.feren...@gmail.com>: > > > > > > > > > *I am not able to get the above point. So when I start Solr with 28g > RAM, > > for all the activities related to Solr it should not go beyond 28g. And > the > > remaining heap will be used for activities other than Solr. Please help > me > > understand.* > > > > Well those 28GB of heap are the memory "reserved" for your Solr > > application, though some parts of the index (not to say all) are > retrieved > > via MMap (if you use the default MMapDirectory) which do not use the heap > > at all. This is a very important part of Lucene/Solr, the heap should be > > sized in a way that let a significant amount of RAM available for the > > index. If not then you rely on the speed of your disk, if you have SSDs > > it's better but reads are still significantly slower with SSDs than with > > direct RAM access. Another thing to keep in mind is that mmap will always > > tries to put things in RAM, this is why I suspect that you swap activity > is > > killing your performance. > > > > 2015-11-02 11:55 GMT+01:00 Modassar Ather <modather1...@gmail.com>: > > > >> Thanks Jim for your response. > >> > >> The remaining size after you removed the heap usage should be reserved > for > >> the index (not only the other system activities). > >> I am not able to get the above point. So when I start Solr with 28g > RAM, > >> for all the activities related to Solr it should not go beyond 28g. And > >> the > >> remaining heap will be used for activities other than Solr. Please help > me > >> understand. > >> > >> *Also the CPU utilization goes upto 400% in few of the nodes:* > >> You said that only machine is used so I assumed that 400% cpu is for a > >> single process (one solr node), right ? > >> Yes you are right that 400% is for single process. > >> The disks are SSDs. > >> > >> Regards, > >> Modassar > >> > >> On Mon, Nov 2, 2015 at 4:09 PM, jim ferenczi <jim.feren...@gmail.com> > >> wrote: > >> > >> > *if it correlates with the bad performance you're seeing. One > important > >> > thing to notice is that a significant part of your index needs to be > in > >> RAM > >> > (especially if you're using SSDs) in order to achieve good > performance.* > >> > > >> > Especially if you're not using SSDs, sorry ;) > >> > > >> > 2015-11-02 11:38 GMT+01:00 jim ferenczi <jim.feren...@gmail.com>: > >> > > >> > > 12 shards with 28GB for the heap and 90GB for each index means that > >> you > >> > > need at least 336GB for the heap (assuming you're using all of it > >> which > >> > may > >> > > be easily the case considering the way the GC is handling memory) > and > >> ~= > >> > > 1TO for the index. Let's say that you don't need your entire index > in > >> > RAM, > >> > > the problem as I see it is that you don't have enough RAM for your > >> index > >> > + > >> > > heap. Assuming your machine has 370GB of RAM there are only 34GB > left > >> for > >> > > your index, 1TO/34GB means that you can only have 1/30 of your > entire > >> > index > >> > > in RAM. I would advise you to check the swap activity on the machine > >> and > >> > > see if it correlates with the bad performance you're seeing. One > >> > important > >> > > thing to notice is that a significant part of your index needs to be > >> in > >> > RAM > >> > > (especially if you're using SSDs) in order to achieve good > >> performance: > >> > > > >> > > > >> > > > >> > > *As mentioned above this is a big machine with 370+ gb of RAM and > Solr > >> > (12 > >> > > nodes total) is assigned 336 GB. The rest is still a good for other > >> > system > >> > > activities.* > >> > > The remaining size after you removed the heap usage should be > reserved > >> > for > >> > > the index (not only the other system activities). > >> > > > >> > > > >> > > *Also the CPU utilization goes upto 400% in few of the nodes:* > >> > > You said that only machine is used so I assumed that 400% cpu is > for a > >> > > single process (one solr node), right ? > >> > > This seems impossible if you are sure that only one query is played > >> at a > >> > > time and no indexing is performed. Best thing to do is to dump stack > >> > trace > >> > > of the solr nodes during the query and to check what the threads are > >> > doing. > >> > > > >> > > Jim > >> > > > >> > > > >> > > > >> > > 2015-11-02 10:38 GMT+01:00 Modassar Ather <modather1...@gmail.com>: > >> > > > >> > >> Just to add one more point that one external Zookeeper instance is > >> also > >> > >> running on this particular machine. > >> > >> > >> > >> Regards, > >> > >> Modassar > >> > >> > >> > >> On Mon, Nov 2, 2015 at 2:34 PM, Modassar Ather < > >> modather1...@gmail.com> > >> > >> wrote: > >> > >> > >> > >> > Hi Toke, > >> > >> > Thanks for your response. My comments in-line. > >> > >> > > >> > >> > That is 12 machines, running a shard each? > >> > >> > No! This is a single big machine with 12 shards on it. > >> > >> > > >> > >> > What is the total amount of physical memory on each machine? > >> > >> > Around 370 gb on the single machine. > >> > >> > > >> > >> > Well, se* probably expands to a great deal of documents, but a > huge > >> > bump > >> > >> > in memory utilization and 3 minutes+ sounds strange. > >> > >> > > >> > >> > - What are your normal query times? > >> > >> > Few simple queries are returned with in a couple of seconds. But > >> the > >> > >> more > >> > >> > complex queries with proximity and wild cards have taken more > than > >> 3-4 > >> > >> > minutes and some times some queries have timed out too where time > >> out > >> > is > >> > >> > set to 5 minutes. > >> > >> > - How many hits do you get from 'network se*'? > >> > >> > More than a million records. > >> > >> > - How many results do you return (the rows-parameter)? > >> > >> > It is the default one 10. Grouping is enabled on a field. > >> > >> > - If you issue a query without wildcards, but with approximately > >> the > >> > >> > same amount of hits as 'network se*', how long does it take? > >> > >> > A query resulting in around half a million record return within a > >> > couple > >> > >> > of seconds. > >> > >> > > >> > >> > That is strange, yes. Have you checked the logs to see if > something > >> > >> > unexpected is going on while you test? > >> > >> > Have not seen anything particularly. Will try to check again. > >> > >> > > >> > >> > If you are using spinning drives and only have 32GB of RAM in > >> total in > >> > >> > each machine, you are probably struggling just to keep things > >> running. > >> > >> > As mentioned above this is a big machine with 370+ gb of RAM and > >> Solr > >> > >> (12 > >> > >> > nodes total) is assigned 336 GB. The rest is still a good for > other > >> > >> system > >> > >> > activities. > >> > >> > > >> > >> > Thanks, > >> > >> > Modassar > >> > >> > > >> > >> > On Mon, Nov 2, 2015 at 1:30 PM, Toke Eskildsen < > >> > t...@statsbiblioteket.dk> > >> > >> > wrote: > >> > >> > > >> > >> >> On Mon, 2015-11-02 at 12:00 +0530, Modassar Ather wrote: > >> > >> >> > I have a setup of 12 shard cluster started with 28gb memory > each > >> > on a > >> > >> >> > single server. There are no replica. The size of index is > around > >> > >> 90gb on > >> > >> >> > each shard. The Solr version is 5.2.1. > >> > >> >> > >> > >> >> That is 12 machines, running a shard each? > >> > >> >> > >> > >> >> What is the total amount of physical memory on each machine? > >> > >> >> > >> > >> >> > When I query "network se*", the memory utilization goes upto > >> 24-26 > >> > gb > >> > >> >> and > >> > >> >> > the query takes around 3+ minutes to execute. Also the CPU > >> > >> utilization > >> > >> >> goes > >> > >> >> > upto 400% in few of the nodes. > >> > >> >> > >> > >> >> Well, se* probably expands to a great deal of documents, but a > >> huge > >> > >> bump > >> > >> >> in memory utilization and 3 minutes+ sounds strange. > >> > >> >> > >> > >> >> - What are your normal query times? > >> > >> >> - How many hits do you get from 'network se*'? > >> > >> >> - How many results do you return (the rows-parameter)? > >> > >> >> - If you issue a query without wildcards, but with approximately > >> the > >> > >> >> same amount of hits as 'network se*', how long does it take? > >> > >> >> > >> > >> >> > Why the CPU utilization is so high and more than one core is > >> used. > >> > >> >> > As far as I understand querying is single threaded. > >> > >> >> > >> > >> >> That is strange, yes. Have you checked the logs to see if > >> something > >> > >> >> unexpected is going on while you test? > >> > >> >> > >> > >> >> > How can I disable replication(as it is implicitly enabled) > >> > >> permanently > >> > >> >> as > >> > >> >> > in our case we are not using it but can see warnings related > to > >> > >> leader > >> > >> >> > election? > >> > >> >> > >> > >> >> If you are using spinning drives and only have 32GB of RAM in > >> total > >> > in > >> > >> >> each machine, you are probably struggling just to keep things > >> > running. > >> > >> >> > >> > >> >> > >> > >> >> - Toke Eskildsen, State and University Library, Denmark > >> > >> >> > >> > >> >> > >> > >> >> > >> > >> > > >> > >> > >> > > > >> > > > >> > > >> > > > > >
