squarespace outage

Apache's "maxclients" option is improperly configured because the system memory is only 2GB in size and the "maxclients" option is configured to 2000, and too many user access processes run out of system memory; Modify the "maxclients" option of the httpd.conf configuration file to reduce this value from 2000 to 1500; Continue to observe that the site is still frequent downtime, and then the "maxclients" option value to 1024, observe a period of time to find, Website service

, service provider, service consumers are long connections between the three, except the monitoring centerThe registry will immediately push events to inform consumers of the presence of a long-connected-aware service provider, service provider downtimeThe Registry and Monitoring Center are all down, without impacting the already running providers and consumers, who cache the provider list locallyRegistries and monitoring centers are optional and service consumers can connect directly to service

and standby two Namenode metadata information in real time (actually Editlog), a shared storage system can be provided, either NFS, QJM (Quorum Journal Manager) or Bookeeper, The active Namenode writes the data to the shared storage system, and standby listens to the system and, once new data is found to be written, reads the data and loads it into its own memory to ensure that its memory state remains basically consistent with the active Namenode, Standby can be quickly cut into active namenod

: 192.168.7.44 redis-cli-h 192.168.7.44-p 6379 shutdown #查看 Sentinel status Redis-cli -H 192.168.7.46-p 26379 info Sentinel #可以看到 The IP address of the Redis server master has become 192.168.7.142. #查看192.168.7.40 status, if configured properly, its main 142 # OK auto-switch has been implemented. # If it's not the main outage, but from the outage, then there will be no switching behavior, only the

First into the CMOS settings of the main interface, select [Power MANAGEMENT Setup], and then select [PWR Lost Resume State], this item has three options. Select the [Keep off] entry, the computer does not start automatically when you call after a power outage. SELECT [Turn on], the computer will start automatically when you call again after a power outage. Selected [Last state], then on behalf of the po

Tags: query error ready to validate close binary mode out ErroToday, in a demo environment, our products experienced the entire engine room power outage, there is a MongoDB binary file corruption, the following is a breakdown of the analysis of the recording process: 1. In the customer support colleagues found that the entire engine room power outage and recovery, 3 MongoDB replication set, 1 hosts on the M

Chapter 1th IntroductionWith the widespread popularization of Internet application, the storage and access of massive data has become the bottleneck problem of system design. For a large-scale Internet application, billions of of PV per day is undoubtedly a very high load on the database. The stability and scalability of the system caused great problems. With data slicing to improve site performance, scaling out the data layer has become the preferred way for architects to develop. Hori

no Fsync, Fsync per second, or fsync each time a write command is executed. The default policy for AOF is Fsync once per second, in which Redis can still maintain good performance and, even if there is a failure, it will lose at most one second of data (Fsync will execute in a background thread, so the main thread can continue to work on the command request). The AOF file is an append-only log file (append only), so the write to the AOF file does not require seek, even if the log contains incom

Tags: high load itblog Read Maintenance will also fully add the DBA implementation principleChapter 1th IntroductionWith the widespread popularization of Internet application, the storage and access of massive data has become the bottleneck problem of system design. For a large-scale Internet application, billions of of PV per day is undoubtedly a very high load on the database. The stability and scalability of the system caused great problems. With data slicing to improve site performance, scal

operation is not logged),To append files but not to overwrite files, Redis startup early reads the file to reconstruct the data, in other words, RedisIf you restart, the write instruction is executed from front to back according to the contents of the log file to complete the recovery of the data. AoF saved is appendonly.aof fileredis.conf Configuration Location:############################## APPEND only MODE ###############################Append aof# By default Redis asynchronously dumps the d

1. OverviewWhen we consider the highly available architecture of the MySQL database, we mainly consider the following aspects:1.1 If the database is down or an unexpected outage, and so on, can restore the availability of the database as soon as possible to reduce downtime, to ensure that the business will not be interrupted due to database failure.1.2 Data for non-primary nodes that are used as backups, read replicas, and so on, should be in real-tim

library I/O line path binlog;2), generate two threads from the library, an I/O thread, a SQL thread, 3) I/O thread will request the binlog of the main library, and writes the resulting binlog log to the relay log (trunk log) file; 4) The SQL thread will read the log in the relay log file and parse it into concrete operation to achieve the same master-slave operation, and the final data is consistent;Problems and SolutionsProblems with MySQL master-slave replication: Data may be lost af

In database PostgreSQL, a client-to-server connection is actually a TCP socket connection, the TCP connection is a virtual connection, the other party exits abnormally (such as a power outage), and the other party continues to maintain the connection. For example, a client computer normally connected to the server, forcibly unplug the power caused by artificial power, restart the computer, and then connected to the server. Using the SQL statement SELE

of a transaction and are deleted when a transaction commits or rolls back. If the log is not rolled back, SQLite will not be able to roll back an incomplete transaction, and the database will be corrupted at some point in the middle of the transaction execution if a system crash or power outage occurs. Rollback logs are typically created and destroyed at the start and end points of a transaction, but there are also some exception rules. If a crash

read the log in the relay log file and parse it into concrete operation to achieve the same master-slave operation, and the final data is consistent;Problems and Solutions Problems with MySQL master-slave replication: Data may be lost after a main library outage There is only one SQL Thread from the library, the main library write pressure is high, replication is likely to delay Workaround: Semi-synchronous Replicati

-20160821160615776-1749314661.png"/> Generate two threads from the library, one I/O thread, and one SQL thread;The I/O thread requests the binlog of the main library and writes the resulting binlog log to the relay log (trunk log) file;The main library generates a log dump thread to path Binlog from the library I/O line;SQL thread, will read the log in the relay log file, and parse into concrete operation, to achieve the master-slave operation consistent, and the final data consistent;Problems

Label:Chapter 1th IntroductionWith the widespread popularization of Internet application, the storage and access of massive data has become the bottleneck problem of system design. For a large-scale Internet application, billions of of PV per day is undoubtedly a very high load on the database. The stability and scalability of the system caused great problems. With data slicing to improve site performance, scaling out the data layer has become the preferred way for architects to develop.

void Join (long millis, int nanos) throws InterruptedexceptionThe maximum time to wait for the thread to terminate is Millis milliseconds + Nanos nanoseconds.Public final void Join () throws InterruptedexceptionWaits for the thread to terminate.Four, two ways to stop the thread 1. Markpublic class Randomcharactergenerator extends Thread {private volatile Boolean do = false; @Overridepublic void Run () {// ... while (!done) {//...} // ...} public void Setdone () {done = true;}}The problem is tha

timed out, etc.ThreeThere is a misunderstanding, once again control the rate of spout acquisition, found that the number of fail is very little, but in a time to complement the data, spout obtained thousands basic data, and Bolt has a business is frequent interaction hbase, resulting in the stream of data accumulation and delay, The UI shows a large number of fail, beginning to think that the processing failed, and later compared to the data found that the calculation results are not many error

interesting, creating a game character is like creating a character object, to get a weapon is like creating a weapon object, encounter monsters,NPCs and so on are objects. then using the knowledge learned to analyze, we found that the object of data are stored in memory, should all know that the memory of the data will disappear after the power outage, but our game after the archive, even if you shut down the computer for a few days, and then into