arangodb/Documentation/DocuBlocks/WalLogfileSlots.md

@brief maximum number of slots to be used in parallel --wal.slots

Configures the amount of write slots the write-ahead log can give to write operations in parallel. Any write operation will lease a slot and return it to the write-ahead log when it is finished writing the data. A slot will remain blocked until the data in it was synchronized to disk. After that, a slot becomes reusable by following operations. The required number of slots is thus determined by the parallelity of write operations and the disk synchronization speed. Slow disks probably need higher values, and fast disks may only require a value lower than the default.