Redis lua graph traversal

find_parent.lua

--"9e4c3550b2961d085916ecdead255cde6b450f6b"
local ret = KEYS[1]
local limit = 100
while limit ~= 0 do
    local pres = redis.pcall("GET", ret)
    if pres == nil or type(pres) == "boolean" then return ret end
    ret = pres
    limit = limit - 1
end
return ret

populate_graph_to_redis.py

import redis
import sys
tot = 1000
split = int(sys.argv[1])
if tot % split != 0 :
    print "first param should divide 1000 perfectly"
    sys.exit(1)
rows = tot/split
cols = split
rc = redis.StrictRedis(host='127.0.0.1')
for i in xrange(rows):
    rc.delete(i*cols)
    for j in xrange(1, cols):
        rc.set(i*cols + j, i*cols + j - 1)

with_lua.py

import redis
import time
import sys
tc = int(sys.argv[1])
rc = redis.StrictRedis(host='127.0.0.1')
def get_root(val):
    return rc.evalsha("9e4c3550b2961d085916ecdead255cde6b450f6b", 1, val)
start = time.time()
print "start", start
for i in xrange(tc):
    get_root(str(i%1000))

end = time.time()
print "end  ", end
print end-start

without_lua.py

import redis
import time
import sys
tc = int(sys.argv[1])
rc = redis.StrictRedis(host='127.0.0.1')
def get_root(val):
    limit = 100
    while limit > 0:
        pres = rc.get(val)
        if pres == None : return val
        val = pres
        limit -= 1
    return val
start = time.time()
print "start", start
for i in xrange(tc):
    get_root(str(i%1000))

end = time.time()
print "end  ", end
print end-start