| 6 | | ALMOS makes hypothesis that [https://www-asim.lip6.fr/trac/tsar TSAR]'s applications have a strong degree of parallelism and/or use a lot of RAM. Applications are standards and use POSIX. They are multiprocesses, multithreads, they work of course in user mode. ALMOS dynamically places threads and physical pages of memory close each other. It is the central problem, because a mismanagement leads to disastrous impact on performances and as a result on consumption. Nevertheless, It is not the only problem to be solved, it will also be necessary to preserving parallelism expressed by applications by allowing parallels access to kernel subsystems such as files system (data, metadata and caches). This parallelism of kernel sub-systems implies more synchronization between several kernel threads accessing to common kernel resources. The kernel has to provide adequate inter-threads synchronization methods dealing with the nature of contention, scalability and the NUMA character of the platform. |
| | 6 | ALMOS makes hypothesis that TSAR's applications have a strong degree of parallelism and/or use a lot of RAM. Applications are standards and use POSIX. They are multiprocesses, multithreads, they work of course in user mode. ALMOS dynamically places threads and physical pages of memory close each other. It is the central problem, because a mismanagement leads to disastrous impact on performances and as a result on consumption. Nevertheless, It is not the only problem to be solved, it will also be necessary to preserving parallelism expressed by applications by allowing parallels access to kernel subsystems such as files system (data, metadata and caches). This parallelism of kernel sub-systems implies more synchronization between several kernel threads accessing to common kernel resources. The kernel has to provide adequate inter-threads synchronization methods dealing with the nature of contention, scalability and the NUMA character of the platform. |
