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Diffstat (limited to 'drivers/staging/zcache/Kconfig')
| -rw-r--r-- | drivers/staging/zcache/Kconfig | 34 |
1 files changed, 33 insertions, 1 deletions
diff --git a/drivers/staging/zcache/Kconfig b/drivers/staging/zcache/Kconfig index 4881839be625..73582705e8c5 100644 --- a/drivers/staging/zcache/Kconfig +++ b/drivers/staging/zcache/Kconfig @@ -1,6 +1,6 @@ config ZCACHE bool "Dynamic compression of swap pages and clean pagecache pages" - depends on (CLEANCACHE || FRONTSWAP) && CRYPTO=y && ZSMALLOC=y + depends on CRYPTO=y && SWAP=y && CLEANCACHE && FRONTSWAP select CRYPTO_LZO default n help @@ -9,3 +9,35 @@ config ZCACHE compression and an in-kernel implementation of transcendent memory to store clean page cache pages and swap in RAM, providing a noticeable reduction in disk I/O. + +config RAMSTER + bool "Cross-machine RAM capacity sharing, aka peer-to-peer tmem" + depends on CONFIGFS_FS=y && SYSFS=y && !HIGHMEM && ZCACHE=y + depends on NET + # must ensure struct page is 8-byte aligned + select HAVE_ALIGNED_STRUCT_PAGE if !64_BIT + default n + help + RAMster allows RAM on other machines in a cluster to be utilized + dynamically and symmetrically instead of swapping to a local swap + disk, thus improving performance on memory-constrained workloads + while minimizing total RAM across the cluster. RAMster, like + zcache2, compresses swap pages into local RAM, but then remotifies + the compressed pages to another node in the RAMster cluster. + +# Depends on not-yet-upstreamed mm patches to export end_swap_bio_write and +# __add_to_swap_cache, and implement __swap_writepage (which is swap_writepage +# without the frontswap call. When these are in-tree, the dependency on +# BROKEN can be removed +config ZCACHE_WRITEBACK + bool "Allow compressed swap pages to be writtenback to swap disk" + depends on ZCACHE=y && BROKEN + default n + help + Zcache caches compressed swap pages (and other data) in RAM which + often improves performance by avoiding I/O's due to swapping. + In some workloads with very long-lived large processes, it can + instead reduce performance. Writeback decompresses zcache-compressed + pages (in LRU order) when under memory pressure and writes them to + the backing swap disk to ameliorate this problem. Policy driving + writeback is still under development. |