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My impression has been that Mongo has great performance as long as your working set is totally in RAM, after which it craters (due to the use of MMAP'd files as
by fiatmoney 14y ago
My impression has been that Mongo has great performance as long as your working set is totally in RAM, after which it craters (due to the use of MMAP'd files as the core storage engine and relying on the OS's paging algos). To what extent is this true on SSDs? Can you get away with a higher working-set-to-RAM ratio?
- mrkurt 14y agoWe've generally found that 1GB of RAM per 10GB of data is best for common Mongo setups. SSDs make a huge impact on the to-disk performance, which does help with the working set. SSDs also help with writes and can help mitigate the infamous global write lock problems in Mongo.
- bifrost 14y agoAny tests on ZFS?