fix empty command which cause titan to crash in parsing command

change empty command's reply error from ErrEmptyArray to ErrEmptyCommand

close the connection when meet empty command

some illegal clients send unreadable command which may cause titan cr… …

…ash. just after read the command we check if it is in command list we support, else will skip it

if a connection send unknown commands 3 times, close it

add expire left seconds metrics

fix expire left time calculating

when set left/delay current seconds(expire), also set other seconds to 0

delete zadd args output

first version of rate limit

1 use rate.limiter to implement limit and read tikv key/value to get … …

…new limit

2 just balance limit base in active titan server num
3 unit test of rate limit passed

qps also can be set burst, its limit also support k/K/m/M suffix

1 change log level--limit not set, to debug …

2 add setlimit.sh

add limit default config items and fix error in config.go

in startSyncNewLimit, just read all match limit once for every comman… …

…d's qps/rate

change got limit log trace

add limit cleared log trace, just log limit is trigger when delay > 0

change limit/commandFunc cost seconds factor from 2 to 1.4

fix titan active time decoding bug

fix limit local percent bug

fix titan active time parsing bug

add updateLimitPercent log

when create commandLimiter, also use localPercent to set limit

fix limitersMgr localPercent using bug and lock before use it

reportLocalStat every globalBalancePeriod,even the commandLimiter is nil

limit can also work on auth-disabled titan server

decrease the lock range in reportStat

reportLocalStat run in itself go routine

1 change how to balance …

2 change qps/rate metrics 3 labels: namespace, command, localip

update some config item's description and log

add limit changed log

commandLimiter store globalQpsLimit/globalRateLimit in int64, use it … …

…to calculate the local limit in updatePercent() and judge if limit is changed, this resolve float precision lost problem

when all titan'a limiter qps is < devideUsage of its weight percent, … …

…add current titan weight again

add showlimit.sh and add a conf parameter for setlimit.sh

1 resolve the problem that titan still process command for remote clo… …

…sed pipelined connection

2 add namespace log for readCommand failure and client processing go routine's exit

1 BytesArray add judge for write eror …

2 use remoteClosed flag to interrupt processing when pipeline connection is closed. if close ctx.Done(channel), and write() again, titan will crush for re-close channel

refactor commandLimiter's qpsLimiter/ratelimiter and their globalLimi… …

…t, lock, localPercent to a LimiterWrapper, and decrease the lock range

fix balance limit's bug

1 in Exec(), add transaction begin, cmd args num, cmd func, reply fun… …

…c metrics

2 cmd args num metrics include the key, which doesn't before
3 in AutoCommit, do adding transaction begin, cmd func, reply func metrics before log.debug()

simplify the msg recv/send log in debug level

fix bug of setting cmd arg num metric in Exec()

add expire/gc round/seek/commit cost metrics

prevent connection more and more: when tikv command cost high, client… …

…s reconnect before it finish

fix bug of connection limit

1 add metrics range, fix cost exceed max value problem …

2 add config item to enable/disable max-connection limit
3 add txn failure metrics in multi/exec scenario

Merge branch 'fpxu_dev' into 'master' …

Fpxu dev

See merge request zz-arch/zhuanzhuan_zzkv!13

1 add example for limit-connection and max-connection-wait in titan.toml

1 fix unlock bug in limit-connection

don't lock s.serverctx.lock when limit-connection disabled

expire seek end in at:now keys to reduce rocksdb tomstone problem

fix a failed case in tests/redis/unit/expire.tcl

expire seek start in last processed expireKeys to reduce rocksdb toms… …

…tone problem

fix expire log

also reduce expire seek range when no expire keys or all expire keys … …

…> now

also reduce expire seek range when no expire keys or all expire keys … …

…> now

comment unsupported string functions in command list, and delete its … …

…redis test case

comment unit test of unsupported string functions in strings_test.go

hash expire-key, it will improve the keys num handled every seconds, … …

…and prevent that current expire-keys region writing node have higher load than other nodes

1 fix runExpire's problem that unhashed goroutine scan hashed expire-key …

2 fix expire_test.go: gc key can get before runExpire/doExpire if expireat < now; add 2 testCases for hash/string expire: check key is deleted and gc key exists after runExpire

unhash expire goroutine use individual limit configuration item、expir… …

…ed&round&seek&commit metrics label

buckets of comand/limit/commandFunc/txn commit cost is too many to lo… …

…ad for dashboard, replace 1.4 with 2, buckets num decrease 50%