我试图对Scotty进行测试,以测试网络I/O效率和整体吞吐量.
为此,我设置了两个用Haskell编写的本地服务器.一个不做任何事情而只是充当API的人.
代码相同
{-# LANGUAGE OverloadedStrings #-}
import Web.Scotty
import Network.Wai.Middleware.RequestLogger
import Control.Monad
import Data.Text
import Control.Monad.Trans
import Data.ByteString
import Network.HTTP.Types (status302)
import Data.Time.Clock
import Data.Text.Lazy.Encoding (decodeUtf8)
import Control.Concurrent
import Network.HTTP.Conduit
import Network.Connection (TLSSettings (..))
import Network.HTTP.Client
import Network
main = do
scotty 4001 $ do
middleware logStdoutDev
get "/dummy_api" $ do
text $ "dummy response"
我写了另一个调用此服务器并返回响应的服务器.
{-# LANGUAGE OverloadedStrings #-}
import Web.Scotty
import Network.Wai.Middleware.RequestLogger
import Control.Monad
import Control.Monad.Trans
import qualified Data.Text.Internal.Lazy as LT
import Data.ByteString
import Network.HTTP.Types (status302)
import …是否可以使用Template Haskell定义函数？例如
convertStringToValue :: String -> Int
convertStringToValue "three" = 3
convertStringToValue "four" = 4
我也有Map [Char] Int.
fromList [("five",5),("six",6)]
我该如何添加功能
convertStringToValue "six" = 6
convertStringToValue "five" = 5
在编译时使用Template Haskell和Map？使用Template Haskell来达到这个目的似乎很愚蠢,但我还是想知道.
如何在Elasticsearch索引中向现有文档添加其他属性.
$ curl -XPUT 'http://localhost:9200/twitter/tweet/1' -d '{
"user" : "kimchy",
"post_date" : "2009-11-15T14:12:12",
"message" : "trying out Elastic Search"
}'
这将在索引中创建一个文档.如何向文档添加属性？假设
"new_attribute":"new_value"
这会将文件修改为
"user" : "kimchy",
"post_date" : "2009-11-15T14:12:12",
"message" : "trying out Elastic Search"
"new_attribute" :"new_value"
我有一个Scotty api服务器,它构造一个Elasticsearch查询,从ES获取结果并呈现json.
与凤凰城和杜松子酒等其他服务器相比,我通过使用BloodHound获得更高的CPU利用率和吞吐量来提供ES响应,但是Gin和Phoenix在内存效率方面比Scotty更好.
Scotty的统计数据
wrk -t30 -c100 -d30s "http://localhost:3000/filters?apid=1&hfa=true"
Running 30s test @ http://localhost:3000/filters?apid=1&hfa=true
30 threads and 100 connections
Thread Stats Avg Stdev Max +/- Stdev
Latency 192.04ms 305.45ms 1.95s 83.06%
Req/Sec 133.42 118.21 1.37k 75.54%
68669 requests in 30.10s, 19.97MB read
Requests/sec: 2281.51
Transfer/sec: 679.28KB
这些统计数据在我的Mac上安装了GHC 7.10.1
处理器信息2.5GHx i5
内存信息8GB 1600 Mhz DDR3
基于轻量级线程的GHC并发性让我印象深刻,但内存效率仍然是一个大问题.
分析内存使用情况产生了以下统计数据
39,222,354,072 bytes allocated in the …参考原始的stackoverflow问题,我试图将金币索引应用于Postgres 9.4中数组对象中的键,但我没有得到第一个答案中所述的结果.
你能否解决这个错误？
我遵循的步骤如下.
第1部分:创建表和索引
CREATE TABLE tracks (id serial, artists jsonb);
CREATE INDEX tracks_artists_gin_idx ON tracks USING gin (artists);
INSERT INTO tracks (id, artists) VALUES (1, '[{"name": "blink-182"}]');
INSERT INTO tracks (id, artists) VALUES (2, '[{"name": "The Dirty Heads"}, {"name": "Louis Richards"}]');
第2部分:查询
SELECT * FROM tracks WHERE artists @> '{"name": "The Dirty Heads"}';
id | artists
----+---------
(0 rows)
此查询提供空结果.
我也尝试使用jsonb_path_opsGIN索引.
替代索引和查询:
DROP INDEX tracks_artists_gin_idx;
CREATE INDEX tracks_artistnames_gin_idx ON tracks USING gin (artists jsonb_path_ops); …我正在尝试使用折叠和追加字节串操作.请参阅下面的代码.
import qualified Data.ByteString.Char8 as C
selectSource :: [String] -> C.ByteString
selectSource xs = C.append (foldl addSource emptySource xs) (C.pack "<head>")
addSource并相应emptySource地定义.用括号看起来有点难看,我想在selectSource函数中删除它们
C.append $ foldl addSource emptySource xs $ C.pack "<head>"
但没有这样做,并得到一个错误消息说
Couldn't match expected type ‘C.ByteString -> C.ByteString’
with actual type ‘C.ByteString’
The first argument of ($) takes one argument,
but its type ‘SourceByteString’ has none
In the second argument of ‘($)’, namely
‘foldl addSource emptySource [] $ C.pack "<head>"’
这有效
C.append (foldl addSource …haskell ×4
indexing ×2
arrays ×1
benchmarking ×1
document ×1
ghc ×1
http-conduit ×1
jsonb ×1
memory ×1
parentheses ×1
postgresql ×1
scotty ×1
sql ×1
updating ×1