Hi Edwin, I’ll let somebody with more knowledge about merge to comment merge aspects. What do you use to merge those cores - merge tool or you run it using Solr’s core API? What is the heap size? How many documents are in those two cores?
Regards, Emir -- Monitoring - Log Management - Alerting - Anomaly Detection Solr & Elasticsearch Consulting Support Training - http://sematext.com/ > On 21 Nov 2017, at 14:20, Zheng Lin Edwin Yeo <edwinye...@gmail.com> wrote: > > Hi Emir, > > Thanks for your reply. > > There are only 1 host, 1 nodes and 1 shard for these 3.5TB. > The merging has already written the additional 3.5TB to another segment. > However, it is still not a single segment, and the size of the folder where > the merged index is supposed to be is now 4.6TB, This excludes the original > 3.5TB, meaning it is already using up 8.1TB of space, but the merging is > still going on. > > The index are currently updates free. We have only index the data in 2 > different collections, and we now need to merge them into a single > collection. > > Regards, > Edwin > > On 21 November 2017 at 16:52, Emir Arnautović <emir.arnauto...@sematext.com> > wrote: > >> Hi Edwin, >> How many host/nodes/shard are those 3.5TB? I am not familiar with merge >> code, but trying to think what it might include, so don’t take any of >> following as ground truth. >> Merging for sure will include segments rewrite, so you better have >> additional 3.5TB if you are merging it to a single segment. But that should >> not last days on SSD. My guess is that you are running on the edge of your >> heap and doing a lot GCs and maybe you will OOM at some point. I would >> guess that merging is memory intensive operation and even if not holding >> large structures in memory, it will probably create a lot of garbage. >> Merging requires a lot of comparison so it is also a possibility that you >> are exhausting CPU resources. >> Bottom line - without more details and some monitoring tool, it is hard to >> tell why it is taking that much. >> And there is also a question if merging is good choice in you case - is >> index static/updates free? >> >> Regards, >> Emir >> -- >> Monitoring - Log Management - Alerting - Anomaly Detection >> Solr & Elasticsearch Consulting Support Training - http://sematext.com/ >> >> >> >>> On 20 Nov 2017, at 17:35, Zheng Lin Edwin Yeo <edwinye...@gmail.com> >> wrote: >>> >>> Hi, >>> >>> Does anyone knows how long usually the merging in Solr will take? >>> >>> I am currently merging about 3.5TB of data, and it has been running for >>> more than 28 hours and it is not completed yet. The merging is running on >>> SSD disk. >>> >>> I am using Solr 6.5.1. >>> >>> Regards, >>> Edwin >> >>
