Update the solutions notebooks and README files to reflect new GitHub repository links for source, ensuring consistency across the documentation.

2025-12-14 17:08:56 +03:00 · 2025-04-30 11:18:28 +03:00
parent abe48e6c23
commit 47a065c126
23 changed files with 788 additions and 788 deletions
--- a/solutions/system_design/query_cache/README-zh-Hans.md
+++ b/solutions/system_design/query_cache/README-zh-Hans.md
@@ -1,6 +1,6 @@
 # 设计一个键-值缓存来存储最近 web 服务查询的结果

-**注意：这个文档中的链接会直接指向[系统设计主题索引](https://github.com/donnemartin/system-design-primer/blob/master/README-zh-Hans.md#系统设计主题的索引)中的有关部分，以避免重复的内容。你可以参考链接的相关内容，来了解其总的要点、方案的权衡取舍以及可选的替代方案。**
+**注意：这个文档中的链接会直接指向[系统设计主题索引](https://github.com/ido777/system-design-primer-update/blob/master/README-zh-Hans.md#系统设计主题的索引)中的有关部分，以避免重复的内容。你可以参考链接的相关内容，来了解其总的要点、方案的权衡取舍以及可选的替代方案。**

 ## 第一步：简述用例与约束条件

@@ -66,11 +66,11 @@

 ### 用例：用户发送了一次请求，命中了缓存

-常用的查询可以由例如 Redis 或者 Memcached 之类的**内存缓存**提供支持，以减少数据读取延迟，并且避免**反向索引服务**以及**文档服务**的过载。从内存读取 1 MB 连续数据大约要花 250 微秒，而从 SSD 读取同样大小的数据要花费 4 倍的时间，从机械硬盘读取需要花费 80 倍以上的时间。<sup><a href=https://github.com/donnemartin/system-design-primer/blob/master/README-zh-Hans.md#每个程序员都应该知道的延迟数>1</a></sup>
+常用的查询可以由例如 Redis 或者 Memcached 之类的**内存缓存**提供支持，以减少数据读取延迟，并且避免**反向索引服务**以及**文档服务**的过载。从内存读取 1 MB 连续数据大约要花 250 微秒，而从 SSD 读取同样大小的数据要花费 4 倍的时间，从机械硬盘读取需要花费 80 倍以上的时间。<sup><a href=https://github.com/ido777/system-design-primer-update/blob/master/README-zh-Hans.md#每个程序员都应该知道的延迟数>1</a></sup>

 由于缓存容量有限，我们将使用 LRU（近期最少使用算法）来控制缓存的过期。

-* **客户端**向运行[反向代理](https://github.com/donnemartin/system-design-primer/blob/master/README-zh-Hans.md#反向代理web-服务器)的 **Web 服务器**发送一个请求
+* **客户端**向运行[反向代理](https://github.com/ido777/system-design-primer-update/blob/master/README-zh-Hans.md#反向代理web-服务器)的 **Web 服务器**发送一个请求
 * 这个 **Web 服务器**将请求转发给**查询 API** 服务
 * **查询 API** 服务将会做这些事情：
    * 分析查询
@@ -206,7 +206,7 @@ class Cache(object):

 解决这些问题的最直接的方法，就是为缓存记录设置一个它在被更新前能留在缓存中的最长时间，这个时间简称为存活时间（TTL）。

-参考 [「何时更新缓存」](https://github.com/donnemartin/system-design-primer/blob/master/README-zh-Hans.md#何时更新缓存)来了解其权衡取舍及替代方案。以上方法在[缓存模式](https://github.com/donnemartin/system-design-primer/blob/master/README-zh-Hans.md#缓存模式)一章中详细地进行了描述。
+参考 [「何时更新缓存」](https://github.com/ido777/system-design-primer-update/blob/master/README-zh-Hans.md#何时更新缓存)来了解其权衡取舍及替代方案。以上方法在[缓存模式](https://github.com/ido777/system-design-primer-update/blob/master/README-zh-Hans.md#缓存模式)一章中详细地进行了描述。

 ## 第四步：架构扩展

@@ -222,16 +222,16 @@ class Cache(object):

 我们将会介绍一些组件来完成设计，并解决架构扩张问题。内置的负载均衡器将不做讨论以节省篇幅。

-**为了避免重复讨论**，请参考[系统设计主题索引](https://github.com/donnemartin/system-design-primer/blob/master/README-zh-Hans.md#系统设计主题的索引)相关部分来了解其要点、方案的权衡取舍以及可选的替代方案。
+**为了避免重复讨论**，请参考[系统设计主题索引](https://github.com/ido777/system-design-primer-update/blob/master/README-zh-Hans.md#系统设计主题的索引)相关部分来了解其要点、方案的权衡取舍以及可选的替代方案。

-* [DNS](https://github.com/donnemartin/system-design-primer/blob/master/README-zh-Hans.md#域名系统)
-* [负载均衡器](https://github.com/donnemartin/system-design-primer/blob/master/README-zh-Hans.md#负载均衡器)
-* [水平拓展](https://github.com/donnemartin/system-design-primer/blob/master/README-zh-Hans.md#水平扩展)
-* [反向代理（web 服务器）](https://github.com/donnemartin/system-design-primer/blob/master/README-zh-Hans.md#反向代理web-服务器)
-* [API 服务（应用层）](https://github.com/donnemartin/system-design-primer/blob/master/README-zh-Hans.md#应用层)
-* [缓存](https://github.com/donnemartin/system-design-primer/blob/master/README-zh-Hans.md#缓存)
-* [一致性模式](https://github.com/donnemartin/system-design-primer/blob/master/README-zh-Hans.md#一致性模式)
-* [可用性模式](https://github.com/donnemartin/system-design-primer/blob/master/README-zh-Hans.md#可用性模式)
+* [DNS](https://github.com/ido777/system-design-primer-update/blob/master/README-zh-Hans.md#域名系统)
+* [负载均衡器](https://github.com/ido777/system-design-primer-update/blob/master/README-zh-Hans.md#负载均衡器)
+* [水平拓展](https://github.com/ido777/system-design-primer-update/blob/master/README-zh-Hans.md#水平扩展)
+* [反向代理（web 服务器）](https://github.com/ido777/system-design-primer-update/blob/master/README-zh-Hans.md#反向代理web-服务器)
+* [API 服务（应用层）](https://github.com/ido777/system-design-primer-update/blob/master/README-zh-Hans.md#应用层)
+* [缓存](https://github.com/ido777/system-design-primer-update/blob/master/README-zh-Hans.md#缓存)
+* [一致性模式](https://github.com/ido777/system-design-primer-update/blob/master/README-zh-Hans.md#一致性模式)
+* [可用性模式](https://github.com/ido777/system-design-primer-update/blob/master/README-zh-Hans.md#可用性模式)

 ### 将内存缓存扩大到多台机器

@@ -239,7 +239,7 @@ class Cache(object):

 * **缓存集群中的每一台机器都有自己的缓存** - 简单，但是它会降低缓存命中率。
 * **缓存集群中的每一台机器都有缓存的拷贝** - 简单，但是它的内存使用效率太低了。
-* **对缓存进行[分片](https://github.com/donnemartin/system-design-primer/blob/master/README-zh-Hans.md#分片)，分别部署在缓存集群中的所有机器中** - 更加复杂，但是它是最佳的选择。我们可以使用哈希，用查询语句 `machine = hash(query)` 来确定哪台机器有需要缓存。当然我们也可以使用[一致性哈希](https://github.com/donnemartin/system-design-primer/blob/master/README-zh-Hans.md#正在完善中)。
+* **对缓存进行[分片](https://github.com/ido777/system-design-primer-update/blob/master/README-zh-Hans.md#分片)，分别部署在缓存集群中的所有机器中** - 更加复杂，但是它是最佳的选择。我们可以使用哈希，用查询语句 `machine = hash(query)` 来确定哪台机器有需要缓存。当然我们也可以使用[一致性哈希](https://github.com/ido777/system-design-primer-update/blob/master/README-zh-Hans.md#正在完善中)。

 ## 其它要点

@@ -247,58 +247,58 @@ class Cache(object):

 ### SQL 缩放模式

-* [读取复制](https://github.com/donnemartin/system-design-primer/blob/master/README-zh-Hans.md#主从复制)
-* [联合](https://github.com/donnemartin/system-design-primer/blob/master/README-zh-Hans.md#联合)
-* [分片](https://github.com/donnemartin/system-design-primer/blob/master/README-zh-Hans.md#分片)
-* [非规范化](https://github.com/donnemartin/system-design-primer/blob/master/README-zh-Hans.md#非规范化)
-* [SQL 调优](https://github.com/donnemartin/system-design-primer/blob/master/README-zh-Hans.md#sql-调优)
+* [读取复制](https://github.com/ido777/system-design-primer-update/blob/master/README-zh-Hans.md#主从复制)
+* [联合](https://github.com/ido777/system-design-primer-update/blob/master/README-zh-Hans.md#联合)
+* [分片](https://github.com/ido777/system-design-primer-update/blob/master/README-zh-Hans.md#分片)
+* [非规范化](https://github.com/ido777/system-design-primer-update/blob/master/README-zh-Hans.md#非规范化)
+* [SQL 调优](https://github.com/ido777/system-design-primer-update/blob/master/README-zh-Hans.md#sql-调优)

 #### NoSQL

-* [键-值存储](https://github.com/donnemartin/system-design-primer/blob/master/README-zh-Hans.md#键-值存储)
-* [文档类型存储](https://github.com/donnemartin/system-design-primer/blob/master/README-zh-Hans.md#文档类型存储)
-* [列型存储](https://github.com/donnemartin/system-design-primer/blob/master/README-zh-Hans.md#列型存储)
-* [图数据库](https://github.com/donnemartin/system-design-primer/blob/master/README-zh-Hans.md#图数据库)
-* [SQL vs NoSQL](https://github.com/donnemartin/system-design-primer/blob/master/README-zh-Hans.md#sql-还是-nosql)
+* [键-值存储](https://github.com/ido777/system-design-primer-update/blob/master/README-zh-Hans.md#键-值存储)
+* [文档类型存储](https://github.com/ido777/system-design-primer-update/blob/master/README-zh-Hans.md#文档类型存储)
+* [列型存储](https://github.com/ido777/system-design-primer-update/blob/master/README-zh-Hans.md#列型存储)
+* [图数据库](https://github.com/ido777/system-design-primer-update/blob/master/README-zh-Hans.md#图数据库)
+* [SQL vs NoSQL](https://github.com/ido777/system-design-primer-update/blob/master/README-zh-Hans.md#sql-还是-nosql)

 ### 缓存

 * 在哪缓存
-    * [客户端缓存](https://github.com/donnemartin/system-design-primer/blob/master/README-zh-Hans.md#客户端缓存)
-    * [CDN 缓存](https://github.com/donnemartin/system-design-primer/blob/master/README-zh-Hans.md#cdn-缓存)
-    * [Web 服务器缓存](https://github.com/donnemartin/system-design-primer/blob/master/README-zh-Hans.md#web-服务器缓存)
-    * [数据库缓存](https://github.com/donnemartin/system-design-primer/blob/master/README-zh-Hans.md#数据库缓存)
-    * [应用缓存](https://github.com/donnemartin/system-design-primer/blob/master/README-zh-Hans.md#应用缓存)
+    * [客户端缓存](https://github.com/ido777/system-design-primer-update/blob/master/README-zh-Hans.md#客户端缓存)
+    * [CDN 缓存](https://github.com/ido777/system-design-primer-update/blob/master/README-zh-Hans.md#cdn-缓存)
+    * [Web 服务器缓存](https://github.com/ido777/system-design-primer-update/blob/master/README-zh-Hans.md#web-服务器缓存)
+    * [数据库缓存](https://github.com/ido777/system-design-primer-update/blob/master/README-zh-Hans.md#数据库缓存)
+    * [应用缓存](https://github.com/ido777/system-design-primer-update/blob/master/README-zh-Hans.md#应用缓存)
 * 什么需要缓存
-    * [数据库查询级别的缓存](https://github.com/donnemartin/system-design-primer/blob/master/README-zh-Hans.md#数据库查询级别的缓存)
-    * [对象级别的缓存](https://github.com/donnemartin/system-design-primer/blob/master/README-zh-Hans.md#对象级别的缓存)
+    * [数据库查询级别的缓存](https://github.com/ido777/system-design-primer-update/blob/master/README-zh-Hans.md#数据库查询级别的缓存)
+    * [对象级别的缓存](https://github.com/ido777/system-design-primer-update/blob/master/README-zh-Hans.md#对象级别的缓存)
 * 何时更新缓存
-    * [缓存模式](https://github.com/donnemartin/system-design-primer/blob/master/README-zh-Hans.md#缓存模式)
-    * [直写模式](https://github.com/donnemartin/system-design-primer/blob/master/README-zh-Hans.md#直写模式)
-    * [回写模式](https://github.com/donnemartin/system-design-primer/blob/master/README-zh-Hans.md#回写模式)
-    * [刷新](https://github.com/donnemartin/system-design-primer/blob/master/README-zh-Hans.md#刷新)
+    * [缓存模式](https://github.com/ido777/system-design-primer-update/blob/master/README-zh-Hans.md#缓存模式)
+    * [直写模式](https://github.com/ido777/system-design-primer-update/blob/master/README-zh-Hans.md#直写模式)
+    * [回写模式](https://github.com/ido777/system-design-primer-update/blob/master/README-zh-Hans.md#回写模式)
+    * [刷新](https://github.com/ido777/system-design-primer-update/blob/master/README-zh-Hans.md#刷新)

 ### 异步与微服务

-* [消息队列](https://github.com/donnemartin/system-design-primer/blob/master/README-zh-Hans.md#消息队列)
-* [任务队列](https://github.com/donnemartin/system-design-primer/blob/master/README-zh-Hans.md#任务队列)
-* [背压](https://github.com/donnemartin/system-design-primer/blob/master/README-zh-Hans.md#背压)
-* [微服务](https://github.com/donnemartin/system-design-primer/blob/master/README-zh-Hans.md#微服务)
+* [消息队列](https://github.com/ido777/system-design-primer-update/blob/master/README-zh-Hans.md#消息队列)
+* [任务队列](https://github.com/ido777/system-design-primer-update/blob/master/README-zh-Hans.md#任务队列)
+* [背压](https://github.com/ido777/system-design-primer-update/blob/master/README-zh-Hans.md#背压)
+* [微服务](https://github.com/ido777/system-design-primer-update/blob/master/README-zh-Hans.md#微服务)

 ### 通信

 * 可权衡选择的方案：
-    * 与客户端的外部通信 - [使用 REST 作为 HTTP API](https://github.com/donnemartin/system-design-primer/blob/master/README-zh-Hans.md#表述性状态转移rest)
-    * 服务器内部通信 - [RPC](https://github.com/donnemartin/system-design-primer/blob/master/README-zh-Hans.md#远程过程调用协议rpc)
-* [服务发现](https://github.com/donnemartin/system-design-primer/blob/master/README-zh-Hans.md#服务发现)
+    * 与客户端的外部通信 - [使用 REST 作为 HTTP API](https://github.com/ido777/system-design-primer-update/blob/master/README-zh-Hans.md#表述性状态转移rest)
+    * 服务器内部通信 - [RPC](https://github.com/ido777/system-design-primer-update/blob/master/README-zh-Hans.md#远程过程调用协议rpc)
+* [服务发现](https://github.com/ido777/system-design-primer-update/blob/master/README-zh-Hans.md#服务发现)

 ### 安全性

-请参阅[「安全」](https://github.com/donnemartin/system-design-primer/blob/master/README-zh-Hans.md#安全)一章。
+请参阅[「安全」](https://github.com/ido777/system-design-primer-update/blob/master/README-zh-Hans.md#安全)一章。

 ### 延迟数值

-请参阅[「每个程序员都应该知道的延迟数」](https://github.com/donnemartin/system-design-primer/blob/master/README-zh-Hans.md#每个程序员都应该知道的延迟数)。
+请参阅[「每个程序员都应该知道的延迟数」](https://github.com/ido777/system-design-primer-update/blob/master/README-zh-Hans.md#每个程序员都应该知道的延迟数)。

 ### 持续探讨

--- a/solutions/system_design/query_cache/README.md
+++ b/solutions/system_design/query_cache/README.md
@@ -1,6 +1,6 @@
 # Design a key-value cache to save the results of the most recent web server queries

-*Note: This document links directly to relevant areas found in the [system design topics](https://github.com/donnemartin/system-design-primer#index-of-system-design-topics) to avoid duplication.  Refer to the linked content for general talking points, tradeoffs, and alternatives.*
+*Note: This document links directly to relevant areas found in the [system design topics](https://github.com/ido777/system-design-primer-update#index-of-system-design-topics) to avoid duplication.  Refer to the linked content for general talking points, tradeoffs, and alternatives.*

 ## Step 1: Outline use cases and constraints

@@ -66,11 +66,11 @@ Handy conversion guide:

 ### Use case: User sends a request resulting in a cache hit

-Popular queries can be served from a **Memory Cache** such as Redis or Memcached to reduce read latency and to avoid overloading the **Reverse Index Service** and **Document Service**.  Reading 1 MB sequentially from memory takes about 250 microseconds, while reading from SSD takes 4x and from disk takes 80x longer.<sup><a href=https://github.com/donnemartin/system-design-primer#latency-numbers-every-programmer-should-know>1</a></sup>
+Popular queries can be served from a **Memory Cache** such as Redis or Memcached to reduce read latency and to avoid overloading the **Reverse Index Service** and **Document Service**.  Reading 1 MB sequentially from memory takes about 250 microseconds, while reading from SSD takes 4x and from disk takes 80x longer.<sup><a href=https://github.com/ido777/system-design-primer-update#latency-numbers-every-programmer-should-know>1</a></sup>

 Since the cache has limited capacity, we'll use a least recently used (LRU) approach to expire older entries.

-* The **Client** sends a request to the **Web Server**, running as a [reverse proxy](https://github.com/donnemartin/system-design-primer#reverse-proxy-web-server)
+* The **Client** sends a request to the **Web Server**, running as a [reverse proxy](https://github.com/ido777/system-design-primer-update#reverse-proxy-web-server)
 * The **Web Server** forwards the request to the **Query API** server
 * The **Query API** server does the following:
    * Parses the query
@@ -206,7 +206,7 @@ The cache should be updated when:

 The most straightforward way to handle these cases is to simply set a max time that a cached entry can stay in the cache before it is updated, usually referred to as time to live (TTL).

-Refer to [When to update the cache](https://github.com/donnemartin/system-design-primer#when-to-update-the-cache) for tradeoffs and alternatives.  The approach above describes [cache-aside](https://github.com/donnemartin/system-design-primer#cache-aside).
+Refer to [When to update the cache](https://github.com/ido777/system-design-primer-update#when-to-update-the-cache) for tradeoffs and alternatives.  The approach above describes [cache-aside](https://github.com/ido777/system-design-primer-update#cache-aside).

 ## Step 4: Scale the design

@@ -222,16 +222,16 @@ It's important to discuss what bottlenecks you might encounter with the initial

 We'll introduce some components to complete the design and to address scalability issues.  Internal load balancers are not shown to reduce clutter.

-*To avoid repeating discussions*, refer to the following [system design topics](https://github.com/donnemartin/system-design-primer#index-of-system-design-topics) for main talking points, tradeoffs, and alternatives:
+*To avoid repeating discussions*, refer to the following [system design topics](https://github.com/ido777/system-design-primer-update#index-of-system-design-topics) for main talking points, tradeoffs, and alternatives:

-* [DNS](https://github.com/donnemartin/system-design-primer#domain-name-system)
-* [Load balancer](https://github.com/donnemartin/system-design-primer#load-balancer)
-* [Horizontal scaling](https://github.com/donnemartin/system-design-primer#horizontal-scaling)
-* [Web server (reverse proxy)](https://github.com/donnemartin/system-design-primer#reverse-proxy-web-server)
-* [API server (application layer)](https://github.com/donnemartin/system-design-primer#application-layer)
-* [Cache](https://github.com/donnemartin/system-design-primer#cache)
-* [Consistency patterns](https://github.com/donnemartin/system-design-primer#consistency-patterns)
-* [Availability patterns](https://github.com/donnemartin/system-design-primer#availability-patterns)
+* [DNS](https://github.com/ido777/system-design-primer-update#domain-name-system)
+* [Load balancer](https://github.com/ido777/system-design-primer-update#load-balancer)
+* [Horizontal scaling](https://github.com/ido777/system-design-primer-update#horizontal-scaling)
+* [Web server (reverse proxy)](https://github.com/ido777/system-design-primer-update#reverse-proxy-web-server)
+* [API server (application layer)](https://github.com/ido777/system-design-primer-update#application-layer)
+* [Cache](https://github.com/ido777/system-design-primer-update#cache)
+* [Consistency patterns](https://github.com/ido777/system-design-primer-update#consistency-patterns)
+* [Availability patterns](https://github.com/ido777/system-design-primer-update#availability-patterns)

 ### Expanding the Memory Cache to many machines

@@ -239,7 +239,7 @@ To handle the heavy request load and the large amount of memory needed, we'll sc

 * **Each machine in the cache cluster has its own cache** - Simple, although it will likely result in a low cache hit rate.
 * **Each machine in the cache cluster has a copy of the cache** - Simple, although it is an inefficient use of memory.
-* **The cache is [sharded](https://github.com/donnemartin/system-design-primer#sharding) across all machines in the cache cluster** - More complex, although it is likely the best option.  We could use hashing to determine which machine could have the cached results of a query using `machine = hash(query)`.  We'll likely want to use [consistent hashing](https://github.com/donnemartin/system-design-primer#under-development).
+* **The cache is [sharded](https://github.com/ido777/system-design-primer-update#sharding) across all machines in the cache cluster** - More complex, although it is likely the best option.  We could use hashing to determine which machine could have the cached results of a query using `machine = hash(query)`.  We'll likely want to use [consistent hashing](https://github.com/ido777/system-design-primer-update#under-development).

 ## Additional talking points

@@ -247,58 +247,58 @@ To handle the heavy request load and the large amount of memory needed, we'll sc

 ### SQL scaling patterns

-* [Read replicas](https://github.com/donnemartin/system-design-primer#master-slave-replication)
-* [Federation](https://github.com/donnemartin/system-design-primer#federation)
-* [Sharding](https://github.com/donnemartin/system-design-primer#sharding)
-* [Denormalization](https://github.com/donnemartin/system-design-primer#denormalization)
-* [SQL Tuning](https://github.com/donnemartin/system-design-primer#sql-tuning)
+* [Read replicas](https://github.com/ido777/system-design-primer-update#master-slave-replication)
+* [Federation](https://github.com/ido777/system-design-primer-update#federation)
+* [Sharding](https://github.com/ido777/system-design-primer-update#sharding)
+* [Denormalization](https://github.com/ido777/system-design-primer-update#denormalization)
+* [SQL Tuning](https://github.com/ido777/system-design-primer-update#sql-tuning)

 #### NoSQL

-* [Key-value store](https://github.com/donnemartin/system-design-primer#key-value-store)
-* [Document store](https://github.com/donnemartin/system-design-primer#document-store)
-* [Wide column store](https://github.com/donnemartin/system-design-primer#wide-column-store)
-* [Graph database](https://github.com/donnemartin/system-design-primer#graph-database)
-* [SQL vs NoSQL](https://github.com/donnemartin/system-design-primer#sql-or-nosql)
+* [Key-value store](https://github.com/ido777/system-design-primer-update#key-value-store)
+* [Document store](https://github.com/ido777/system-design-primer-update#document-store)
+* [Wide column store](https://github.com/ido777/system-design-primer-update#wide-column-store)
+* [Graph database](https://github.com/ido777/system-design-primer-update#graph-database)
+* [SQL vs NoSQL](https://github.com/ido777/system-design-primer-update#sql-or-nosql)

 ### Caching

 * Where to cache
-    * [Client caching](https://github.com/donnemartin/system-design-primer#client-caching)
-    * [CDN caching](https://github.com/donnemartin/system-design-primer#cdn-caching)
-    * [Web server caching](https://github.com/donnemartin/system-design-primer#web-server-caching)
-    * [Database caching](https://github.com/donnemartin/system-design-primer#database-caching)
-    * [Application caching](https://github.com/donnemartin/system-design-primer#application-caching)
+    * [Client caching](https://github.com/ido777/system-design-primer-update#client-caching)
+    * [CDN caching](https://github.com/ido777/system-design-primer-update#cdn-caching)
+    * [Web server caching](https://github.com/ido777/system-design-primer-update#web-server-caching)
+    * [Database caching](https://github.com/ido777/system-design-primer-update#database-caching)
+    * [Application caching](https://github.com/ido777/system-design-primer-update#application-caching)
 * What to cache
-    * [Caching at the database query level](https://github.com/donnemartin/system-design-primer#caching-at-the-database-query-level)
-    * [Caching at the object level](https://github.com/donnemartin/system-design-primer#caching-at-the-object-level)
+    * [Caching at the database query level](https://github.com/ido777/system-design-primer-update#caching-at-the-database-query-level)
+    * [Caching at the object level](https://github.com/ido777/system-design-primer-update#caching-at-the-object-level)
 * When to update the cache
-    * [Cache-aside](https://github.com/donnemartin/system-design-primer#cache-aside)
-    * [Write-through](https://github.com/donnemartin/system-design-primer#write-through)
-    * [Write-behind (write-back)](https://github.com/donnemartin/system-design-primer#write-behind-write-back)
-    * [Refresh ahead](https://github.com/donnemartin/system-design-primer#refresh-ahead)
+    * [Cache-aside](https://github.com/ido777/system-design-primer-update#cache-aside)
+    * [Write-through](https://github.com/ido777/system-design-primer-update#write-through)
+    * [Write-behind (write-back)](https://github.com/ido777/system-design-primer-update#write-behind-write-back)
+    * [Refresh ahead](https://github.com/ido777/system-design-primer-update#refresh-ahead)

 ### Asynchronism and microservices

-* [Message queues](https://github.com/donnemartin/system-design-primer#message-queues)
-* [Task queues](https://github.com/donnemartin/system-design-primer#task-queues)
-* [Back pressure](https://github.com/donnemartin/system-design-primer#back-pressure)
-* [Microservices](https://github.com/donnemartin/system-design-primer#microservices)
+* [Message queues](https://github.com/ido777/system-design-primer-update#message-queues)
+* [Task queues](https://github.com/ido777/system-design-primer-update#task-queues)
+* [Back pressure](https://github.com/ido777/system-design-primer-update#back-pressure)
+* [Microservices](https://github.com/ido777/system-design-primer-update#microservices)

 ### Communications

 * Discuss tradeoffs:
-    * External communication with clients - [HTTP APIs following REST](https://github.com/donnemartin/system-design-primer#representational-state-transfer-rest)
-    * Internal communications - [RPC](https://github.com/donnemartin/system-design-primer#remote-procedure-call-rpc)
-* [Service discovery](https://github.com/donnemartin/system-design-primer#service-discovery)
+    * External communication with clients - [HTTP APIs following REST](https://github.com/ido777/system-design-primer-update#representational-state-transfer-rest)
+    * Internal communications - [RPC](https://github.com/ido777/system-design-primer-update#remote-procedure-call-rpc)
+* [Service discovery](https://github.com/ido777/system-design-primer-update#service-discovery)

 ### Security

-Refer to the [security section](https://github.com/donnemartin/system-design-primer#security).
+Refer to the [security section](https://github.com/ido777/system-design-primer-update#security).

 ### Latency numbers

-See [Latency numbers every programmer should know](https://github.com/donnemartin/system-design-primer#latency-numbers-every-programmer-should-know).
+See [Latency numbers every programmer should know](https://github.com/ido777/system-design-primer-update#latency-numbers-every-programmer-should-know).

 ### Ongoing