# Skip GPU benchmarks
Going through them briefly: this is not a distributed system and it has a very hard limit on scalability or availability. You can deploy a “SpacetimeDB cluster”, meaning a primary instance and several followers with eventually consistent replication (emphasis on eventually consistent; the WAL is eventually consistent, the replication is too, there’s a lot of margin for things to go wrong here), but your whole system is bottlenecked by the CPU and RAM capacity of the machine where your main SpacetimeDB instance is deployed. You need enough CPU for your database to execute all the queries, but also for your whole application to execute all its application logic, as again the application lives inside the database. You need enough RAM to fit all your database’s data in-memory. SpacetimeDB is not disk-backed at all; it just flushes a WAL to disk (and periodically, snapshots that make recovering from the WAL quicker on restarts). If your dataset grows larger than RAM, your database (and your application, which are the same thing) will fail over. The only option for scalability here is vertical: buying a bigger machine to run your database.。业内人士推荐新收录的资料作为进阶阅读
。新收录的资料是该领域的重要参考
Graham, known for his long essays on startups, economics, and the tech industry, was one of the first to comment on the importance of taste in a 2002 essay in which he claimed “taste” is not objective and that “we need good taste to make good things.”
Check the video out here:，这一点在新收录的资料中也有详细论述
The caller provides context and modifies the behavior of get_user_pages() via flags. Of particular interest is the FOLL_FORCE flag, which mem_rw() passes. This flag causes check_vma_flags (the access validation logic within get_user_pages()) to ignore writes to unwritable pages and allow the lookup to continue. The “punch through” semantics are attributed entirely to FOLL_FORCE. (comments my own)