Under 2 minutes, could probably start optimizing as I did for rust, but it's good enough for now

This commit is contained in:
Fabian Schmidt 2024-08-30 15:33:40 +02:00
parent 5bb2363eee
commit 4d586c809e

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@ -33,38 +33,58 @@ function print_measurements(stations::Dict{String,StationMeasurements})
print("}")
end
function merge(stations_vec::Vector{Dict{String,StationMeasurements}})
merged = Dict{String,StationMeasurements}()
for stations in stations_vec
for (city, sm) in stations
if haskey(merged, city)
merged_sm = merged[city]
sm.min = ifelse(merged_sm.min < sm.min, merged_sm.min, sm.min)
sm.max = ifelse(merged_sm.max > sm.max, merged_sm.max, sm.max)
sm.sum += merged_sm.sum
sm.count += merged_sm.count
else
merged[city] = sm
end
end
end
merged
end
function process_chunk(data, chunk)
stations = Dict{String,StationMeasurements}()
for i in eachindex(chunk)
if i == 1
continue
end
line = String(data[chunk[i-1]:chunk[i]-1])
station, temp_str = rsplit(line, ";")
temp = parse(Float32, temp_str)
if haskey(stations, station)
sm = stations[station]
sm.min = ifelse(temp < sm.min, temp, sm.min)
sm.max = ifelse(temp > sm.max, temp, sm.max)
sm.sum += temp
sm.count += 1
else
stations[station] = StationMeasurements(temp, temp, temp, 1)
end
end
stations
end
function main()
open("../../../measurements.txt", "r") do f
println("Start")
sz = Base.stat(f).size
data = mmap(f, Vector{UInt8}, sz)
idxs = findall(isequal(0x0a), data)
stations = Dict{String,StationMeasurements}()
iteration = 0
last_idx = 1
for i in eachindex(idxs)
if iteration % 1000000 == 0 && iteration > 0
print("\x1b[J\x1b[H")
percent = round((iteration / 1000000000) * 100; digits=2)
println("$(percent)%")
end
line = String(data[last_idx:idxs[i]-1])
last_idx = idxs[i] + 1
station, temp_str = rsplit(line, ";")
temp = parse(Float32, temp_str)
if haskey(stations, station)
sm = stations[station]
sm.min = ifelse(temp < sm.min, temp, sm.min)
sm.max = ifelse(temp > sm.max, temp, sm.max)
sm.sum += temp
sm.count += 1
else
stations[station] = StationMeasurements(temp, temp, temp, 1)
end
iteration += 1
idxs_chunks = collect(Iterators.partition(idxs, length(idxs) ÷ Threads.nthreads()))
tasks = map(idxs_chunks) do chunk
Threads.@spawn process_chunk(data, chunk)
end
stations_vec = fetch.(tasks)
stations = merge(stations_vec)
print_measurements(stations)
println("End")
end
end