To pile on a bit: Your *.fdt files contain “stored=true” data. By and large I ignore them for this discussion. Say I execute a query with “rows=10”. The fdt (and fdx) files are only accessed for the 10 docs returned so they have little impact on query time. Or rather, they have a reasonably constant effect on query time. So when trying to get a feel for the RAM/index-size ratio these can be pretty much ignored.
Second, you say you ran your tests for 8 hours. How distinct are the queries? If you run some relatively small set of queries, all the bits of the index that you need will be loaded into RAM very early and just repeating the same set of queries a zillion times measures nothing interesting. I like at least 5,000 distinct queries that I then randomize when load testing, more if possible and all real user queries if possible. If you can’t get real user queries, you have to guess I’m afraid. Best, Erick > On Apr 15, 2019, at 8:17 AM, BlackIce <blackice...@gmail.com> wrote: > > I'm not that proficient with Solr.. I used it, but I'd yet have to fully > dive into it, but this topic really interests me. > > In those 8 hour tests, does ALL information get accessed, or just partial? > That could be a reason as to why you don't see any difference, that the > test in that time period only accesses partial amount of the Information > and in this time period it only accesses an amount of information which > fits into RAM in both cases... > > SSD's will be slower as RAM anyway > > On Mon, Apr 15, 2019 at 4:53 PM SOLR4189 <klin892...@yandex.ru> wrote: > >> No, I don't load index to RAM, but I run 8 hours queries, so OS must load >> necessary files (segments) to RAM during my tests. So in the case where I >> set 25GB for RAM, not all files will be loaded to RAM and I thought I'll >> see >> degradation in queries times, but I didn't >> >> >> >> -- >> Sent from: http://lucene.472066.n3.nabble.com/Solr-User-f472068.html >>
