3 ms·
Call me skeptical: >When testing read performance on SeaweedFS, it basically becomes performance test your hard drive's random read speed. Hard Drive usually g
by tw04 10y ago
Call me skeptical:
>When testing read performance on SeaweedFS, it basically becomes performance test your hard drive's random read speed. Hard Drive usually get 100MB/s~200MB/s.
There are no modern hard drives that get 100-200MB/sec on RANDOM reads. Random ends up being an exercise in IOPS not throughput, and there's absolutely no way you're pulling enough IOPS out of a SAS or SATA hard drive to get anywhere NEAR 100-200MB/sec on random workloads. I get the "it's the software dummy" thing everyone is so hyped about, but if you know THAT little about the underlying hardware and how it functions, you shouldn't be writing filesystems.
Also - what's the protection mechanism for files? If there is none, I literally have no idea what the purpose of this FS is. Under what circumstances would I need a giant slow data storage tier that has no redundancy to speak of?
- discordianfish 10y agoAgree, that sentence doesn't make sense. But I think the point is simply that accessing data doesn't have any overhead, so you benchmarking your disks. Given the design, that seems likely. > Also - what's the protection mechanism for files? If there is none, I literally have no idea what the purpose of this FS is. Under what circumstances would I need a giant slow data storage tier that has no redundancy to speak of? Caches, that's what makes me interested in this (having to cache lots of images). We're using mogilefs for this currently.
- jdcarter 10y agoRe protection, see: https://github.com/chrislusf/seaweedfs#rack-aware-and-data-center-aware-replication https://github.com/chrislusf/seaweedfs#rack-aware-and-data-c... (Not an author or anything, just found this project today, and it's interesting enough for me to test it out.) Edit to add: I've done some testing, SeaweedFS definitely replicates. When the client wants to read from a volume, it should do a lookup and Seaweed will return the URLs of all volume servers which are up at the moment. So far I've just been testing 2-way replication with one server down at a time; it works fine.
- pdeuchler 10y agoMy best guess is these numbers are from short benchmarks they ran on SSD's before they reached the steady state... I've pretty frequently been able to hit upwards of 200 mb/s when running short (read: misleading) benchmarks.
- chrislusf 10y agoSorry for my wording, if it is misleading. I am only saying the SeaweedFS code does not try to do anything unnecessary, so you can extract most of the performance juice out of your hard drive or SSD.