服务器P在主机p上运行，且对其恢复日志文件持有排它文件锁定。
Server P is running on host P and holds an exclusive file lock for its own recovery log files.
主日志文件建立了一个固定大小的存储空间，这是分配给恢复日志文件的。
Primary log files establish a fixed amount of storage allocated to the recovery log files.
恢复日志文件选项恢复备份映像中保存的日志文件(适用于在线备份和恢复)。
Restore log file option restores the log files saved in the backup image (more applicable for online backup and restore).
要避免这样的危险发生，WebSphereApplicationServer使用网络文件锁定技术来确保对恢复日志文件的排它访问。
To prevent such problems from occurring, WebSphere Application Server USES network file locking technology to ensure exclusive access to recovery log files.
要保持恢复日志文件的完整性，一次只能允许单个客户端流程对其进行访问。 通过使用先前讨论到的排它网络文件锁定来确保访问的进行。
To maintain the integrity of a recovery log file, only a single client process can access the log at a time; this access can be assured using the exclusive network file locks discussed previously.
注意我们仅仅着眼于恢复日志而不是数据库文件。
Notice we are only looking at the recovery log — not database files.
此进程在回滚、重启恢复和前滚期间读取日志文件。
This process reads log files during rollback, restart recovery and roll forward.
事务日志存储为连续的磁盘文件(有时存储在原始分区中)，并且一般只是用于写入而不用于读取，回滚或恢复的情况例外。
The transaction log is stored as a sequential disk file (or sometimes in a raw partition) and will generally only be written to, not read from, except in the case of rollback or recovery.
虽然向一个日志文件发送消息相当有用，但是很多时候您可能还想在发生不可恢复的异常时显示一个用户友好的错误消息。
Although sending messages to a log file can be quite useful, there are often times when you would also like to display a user-friendly error message in the event of an unrecoverable exception.
崩溃恢复是对日志文件进行处理，确保所有已提交的事务被写到磁盘，所有未提交的事务被回滚。
Crash recovery is the processing of the log files, making sure all committed transactions are written to disk and uncommitted transactions are rolled back.
例如，为了将数据恢复到星期三工作结束时，需要星期一、星期二和星期三的差异备份镜像(或星期三的日志文件)。
For example, to recover data to the end of business day Wednesday, you would need the delta backup images for Monday, Tuesday, and Wednesday (or Wednesday's log files).
在日志文件系统出现之前，系统崩溃后恢复文件系统往往要耗费大量时间。
Before the advent of journaling filesystems, recovery of a filesystem after a system crash often took a long time.
一旦系统发生崩溃，日志文件就会起到一个检查点的作用，用于恢复未保存的信息，防止损坏文件系统元数据。
If a crash occurs, the journal can be used as a checkpoint to recover unsaved information and avoid corrupting file system metadata.
使用文件锁定确保对组成恢复日志的文件的排它访问。
File locking is used to ensure exclusive access to the files that make up a recovery log.
该进程为可恢复的数据库管理日志文件。
总之，日志文件系统就是一种具有故障恢复能力的文件系统，它利用日志来记录尚未提交到文件系统的修改，以防止元数据破坏(请参见图1)。
To sum up, journaling file systems are fault-resilient file systems that use a journal to log changes before they're committed to the file system to avoid metadata corruption (see Figure 1).
JFS2支持预定的日志记录方式，可以提高较高的性能，并实现亚秒级文件系统恢复。
JFS2 supports ordered journaling for high performance with sub-second file system recovery.
db2loggr：该进程操作日志文件用于处理事务进程和恢复。
Db2loggr: For manipulating log files to handle transaction processing and recovery.
将softmax参数设置为较低的数字，以便更频繁地将日志控制文件写入磁盘，因而在崩溃恢复之后，数据库的恢复时间更少。
The softmax parameter is set to a lower number, so that the log control file is written to disk more often, and thus after a crash recovery the database may need less time to recover.
最后，数据库和表空间的在线备份镜像将包括一组日志文件，在将备份镜像恢复到某个一致的时间点时，这些文件是必需的。
Finally, online backup images of databases and table Spaces will include the set of log files necessary to restore and recover the backup image to a consistent point in time.
对于许多应用程序，尤其是日志文件和数据库，这种恢复删除文件的方法非常有用。
This method of recovering deleted files is handy for many applications, especially log files and databases.
当ROLLFORWARD实用程序需要使用日志文件来恢复数据库时，就会检索它们。
They are retrieved when the ROLLFORWARD utility needs to use them to restore a database.
多亏了日志，数百G的文件系统元数据几乎能在瞬间恢复到一致性的状态。
Thanks to the journal, hundreds of Gigabytes of filesystem meta-data can be brought to a consistent state almost instantaneously.
当然，XFS也是一种日志记录文件系统，它允许意外重新引导后的快速恢复。
Of course, XFS is a journaling filesystem, allowing for fast recovery after an unexpected reboot.
日志文件系统是使用日志来缓冲文件系统的修改(同时也可以应用于紧急故障恢复)的，但可以根据记录的时间与内容采取不同的策略。
Journaling file systems use a journal to buffer changes to the file system (which is also used in crash recovery) but can use different strategies for when and what is journaled.
从未归档联机日志文件的丢失中恢复。
恢复后，如果将事务日志文件播放到恢复的数据库，搜索索引可能变得与数据库不同步。
The search index can become unsynchronized with the database after a recovery if transaction log files are played into the recovered database.
如果logretain设置成“Recovery”或者userexit设置成“Yes”(请参阅下一节)，将保留活动日志文件，而且这些文件将变成联机归档日志文件，以便在前滚恢复中使用。
If logretain is set to "recovery" or userexit is set to "Yes" (see below), the active log files will be retained and become online archive log files for use in roll-forward recovery.
本主题说明为本地连续复制(LCR)启用的活动数据库及其日志文件已损坏时，如何恢复数据。
This topic explains how to recover data when an active database and its log files that are enabled for local continuous replication (LCR) become corrupt.
另外，与较传统的文件系统方法(比如那些依赖于fsck的系统)相比，日志文件系统大大地缩短了系统崩溃的恢复时间。
Additionally, the crash recovery time for journaling file systems is dramatically reduced compared to more traditional file system methods (such as those that rely on FSCK).
应用推荐