Fast input/output in a content-addressable storage architecture with paged metadata

A system for minimizing read amplification for input/output (IO) where metadata is not in random access memory (RAM), comprising:

• a memory comprising computer-executable instructions;
• and
• a processor executing the computer-executable instructions, the computer-executable instructions when executed by the processor cause the processor to perform operations comprising:
• reading a l_md_page and corresponding lp_md_page from a storage device in a dual distributed layered architecture, the l_md_page specifies a metadata page that persists in a solid state drive and having logical addresses of metadata, and the lp_md_page associates logical block addresses (LBAs) with corresponding physical locations for the metadata;
• concatenating the l_md_page and the lp_md_page;
• storing the concatenated pages in the solid state disk;
• wherein reading the reading the l_md_page and the lp_md_page includes loading the concatenated pages in a single command;
• reading data for a redundant array of independent disks (RAID) stripe according to an associated physical offset in the lp_md_page;
• accessing a stripe counter from the lp_md_page;
• comparing the stripe counter from the lp_md_page to a stripe counter held in memory;
• and
• upon determining the stripe counter from the lp_md_page is the same:
• determining the data is valid;
• and
• reading the data according to associated physical offset in the lp_md_page and while bypassing a data module for the data.

A computer program product embodied on a non-transitory computer readable medium, the computer program product including instructions that, when executed by a computer causes the computer to perform operations comprising:

• reading a l_md_page and corresponding lp_md_page from a storage device in a dual distributed layered architecture, the l_md_page specifies a metadata page that persists in a solid state drive and having logical addresses of metadata, and the lp_md_page associates logical block addresses (LBAs) with corresponding physical locations for the metadata;
• concatenating the l_md_page and the lp_md_page;
• storing the concatenated pages in the solid state disk;
• wherein reading the reading the l_md_page and the lp_md_page includes loading the concatenated pages in a single command:
• reading data for a redundant array of independent disks (RAID) stripe according to an associated physical offset in the lp_md_page;
• accessing a stripe counter from the lp_md_page;
• comparing the stripe counter to from the lp_md_page to a stripe counter held in memory;
• and
• upon determining the stripe counter from the lp_md_page is the same:
• determining the data is valid;
• and
• reading the data according to associated physical offset in the lp_md_page and while bypassing a data module for the data.