Anuragkumarjoy

 In Oracle, LOB means Large Object.

You use a LOB column when the data is too large, unstructured, or not practical to store in normal VARCHAR2 / RAW columns.

When do we use LOB?

Use LOBs when you need to store:

1) Large tex...

 

Short Answer

No — HugePages do not directly increase disk I/O throughput or IOPS.

What they do improve is memory-management efficiency for Oracle’s SGA, which can indirectly improve overall database performance in workloads where CPU overhead, memory translation, and buffer cache ef...

 

One-line explanation

HugePages make Oracle’s SGA memory easier for the OS and CPU to manage, but they do not make the disk, SAN, ASM, or file system read/write data any faster.

Why exactly they do not help I/O

Let’s break the full path into layers:

1. Storage / I/O layer

This is where physical I/O happens:

Disk / SSD ...

 

1. Normal OS Page vs HugePage (Fundamentals)Default Linux memory pagesStandard page size: 4 KBEvery memory access uses page tables to translate virtual → physicalLarge SGA → millions of page table entries (PTEs)HugePages (HugeTLB)Larger page size: typically 2 MB (or 1 GB on some systems)Reduces:Page table entriesTLB...

 

🔎 PART 1 — How to Identify Index is Causing Performance Issue✅ Step 1: Find Slow SQL (Entry Point)

Start from Top SQL, not from the index.

SELECT sql_id, executions, elapsed_time, buffer_gets
FROM v$sql
ORDER BY elapsed_time DESC FETCH FIRST 10 ROWS ONLY;

👉 Pick the problematic SQL

...