From bcfed7088863746e096c0d17f5c6b19b6d57ffb8 Mon Sep 17 00:00:00 2001
From: Kerollmops <clement@meilisearch.com>
Date: Mon, 9 Dec 2024 10:08:02 +0100
Subject: [PATCH 1/2] Revert "Merge #5125"

This reverts commit 9a9383643f9a6b5ee9ab2ace3e9d63b920d94a53, reversing
changes made to cac355bfa7e72ca3c5c02cacb4f2fcd3f2dd336e.
---
 crates/meilisearch/src/option.rs | 9 ++++-----
 1 file changed, 4 insertions(+), 5 deletions(-)

diff --git a/crates/meilisearch/src/option.rs b/crates/meilisearch/src/option.rs
index 7c59f0607..7e87a5a2c 100644
--- a/crates/meilisearch/src/option.rs
+++ b/crates/meilisearch/src/option.rs
@@ -654,9 +654,8 @@ impl Opt {
 
 #[derive(Debug, Default, Clone, Parser, Deserialize)]
 pub struct IndexerOpts {
-    /// Specifies the maximum resident memory that Meilisearch can use for indexing.
-    /// By default, Meilisearch limits the RAM usage to 5% of the total available memory.
-    /// Note that the underlying store utilizes memory-mapping and makes use of the rest.
+    /// Sets the maximum amount of RAM Meilisearch can use when indexing. By default, Meilisearch
+    /// uses no more than two thirds of available memory.
     #[clap(long, env = MEILI_MAX_INDEXING_MEMORY, default_value_t)]
     #[serde(default)]
     pub max_indexing_memory: MaxMemory,
@@ -715,7 +714,7 @@ impl TryFrom<&IndexerOpts> for IndexerConfig {
     }
 }
 
-/// A type used to detect the max resident memory available and use 5% of it.
+/// A type used to detect the max memory available and use 2/3 of it.
 #[derive(Debug, Clone, Copy, Deserialize, Serialize)]
 pub struct MaxMemory(Option<Byte>);
 
@@ -729,7 +728,7 @@ impl FromStr for MaxMemory {
 
 impl Default for MaxMemory {
     fn default() -> MaxMemory {
-        MaxMemory(total_memory_bytes().map(|bytes| bytes * 5 / 100).map(Byte::from_u64))
+        MaxMemory(total_memory_bytes().map(|bytes| bytes * 2 / 3).map(Byte::from_u64))
     }
 }
 

From f5dd8dfc3e57cfa36fc3ccbefe73de0706a156fd Mon Sep 17 00:00:00 2001
From: Kerollmops <clement@meilisearch.com>
Date: Mon, 9 Dec 2024 10:26:30 +0100
Subject: [PATCH 2/2] Rollback max memory usage changes

---
 crates/milli/src/update/new/indexer/mod.rs | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/crates/milli/src/update/new/indexer/mod.rs b/crates/milli/src/update/new/indexer/mod.rs
index 9ee7577a5..59088bd47 100644
--- a/crates/milli/src/update/new/indexer/mod.rs
+++ b/crates/milli/src/update/new/indexer/mod.rs
@@ -80,6 +80,15 @@ where
     let mut bbbuffers = Vec::new();
     let finished_extraction = AtomicBool::new(false);
 
+    // We reduce the actual memory used to 5%. The reason we do this here and not in Meilisearch
+    // is because we still use the old indexer for the settings and it is highly impacted by the
+    // max memory. So we keep the changes here and will remove these changes once we use the new
+    // indexer to also index settings. Related to #5125 and #5141.
+    let grenad_parameters = GrenadParameters {
+        max_memory: grenad_parameters.max_memory.map(|mm| mm * 5 / 100),
+        ..grenad_parameters
+    };
+
     // We compute and remove the allocated BBQueues buffers capacity from the indexing memory.
     let minimum_capacity = 50 * 1024 * 1024 * pool.current_num_threads(); // 50 MiB
     let (grenad_parameters, total_bbbuffer_capacity) = grenad_parameters.max_memory.map_or(