internals: Remove last_log from the internal context v1 APPLIED

Louis Solofrizzo: 1
 internals: Remove last_log from the internal context

 4 files changed, 4 insertions(+), 21 deletions(-)

[PATCH] internals: Remove last_log from the internal context Export this patch

May cause some bugs, and it is mostly useless anyway. I've reworked
AE response a bit to simplify it. We now do a DB write per log applied,
instead of one write per AE call.

Signed-off-by: Louis Solofrizzo <lsolofrizzo@scaleway.com>
---
 libfloat.h |  1 -
 log.c      | 22 ++++------------------
 raft.c     |  1 -
 snapshot.c |  1 -
 4 files changed, 4 insertions(+), 21 deletions(-)

diff --git a/libfloat.h b/libfloat.h
index e5494b7..fe352d5 100644
--- a/libfloat.h
+++ b/libfloat.h
@@ -67,7 +67,6 @@ struct libfloat_ctx_s {
     khash_t(libfloat_node_id_t) *nodes;                 /*!< Hashtable of nodes */
     libfloat_node_t             *leader;                /*!< Current Leader (can be NULL) */
     libfloat_node_t             *me;                    /*!< My node in the cluster */
-    libfloat_log_entry_t        *last_log;              /*!< Last log committed */
 
     uint32_t                    timeout_elapsed;        /*!< Current time elasped between two heartbeats */
     uint32_t                    election_timeout_rand;  /*!< Randomized election time */
diff --git a/log.c b/log.c
index bd03d67..0c8bcc9 100644
--- a/log.c
+++ b/log.c
@@ -126,7 +126,6 @@ bool libfloat_add_log(libfloat_ctx_t *ctx, libfloat_commit_type_t commit_type, l
 
     libfloat_log_add_node_ack(ctx, entry, ctx->me->id);
     ctx->timeout_elapsed = 0;
-    ctx->last_log = entry;
     libfloat_set_current_commit_index(ctx, entry->id);
 
     for_every_node(ctx, node, {
@@ -378,7 +377,8 @@ end:
 
 void libfloat_append_entries_receive(libfloat_ctx_t *ctx, libfloat_rpc_append_entries_t *req, libfloat_rpc_append_entries_response_t *resp)
 {
-    libfloat_node_t *node = libfloat_get_node(ctx, req->leader_id);
+    libfloat_node_t             *node = libfloat_get_node(ctx, req->leader_id);
+    libfloat_entry_id_t         last_written_entry_id = 0;
 
     if (ctx->gray_failures.checking == true)
     {
@@ -510,7 +510,6 @@ response:
         if (iterator != kh_end(ctx->persistent.log))
         {
             /* This log was already committed, ignore it */
-            resp->current_index = req->entries[i]->id;
             continue;
         }
 
@@ -549,7 +548,7 @@ response:
                 goto end;
             }
 
-            ctx->last_log = log;
+            libfloat_set_current_commit_index(ctx, req->entries[i]->id);
         }
         else if (ctx->is_snapshotting)
         {
@@ -563,23 +562,10 @@ response:
             log->data->buf = ctx->malloc(log->data->len);
             memcpy(log->data->buf, req->entries[i]->data->buf, log->data->len);
         }
-
-        resp->current_index = log->id;
     }
 
 end:
-    if (!resp->success)
-        resp->current_index = ctx->persistent.commit_index;
-    else
-    {
-        if (resp->current_index == 0)
-            resp->current_index = ctx->persistent.commit_index;
-        else
-        {
-            if (!ctx->is_snapshotting && ctx->last_log)
-                libfloat_set_current_commit_index(ctx, ctx->last_log->id);
-        }
-    }
+    resp->current_index = ctx->persistent.commit_index;
 
     if (node != NULL && req->n_entries > 0)
     {
diff --git a/raft.c b/raft.c
index 8f10661..2f7415d 100644
--- a/raft.c
+++ b/raft.c
@@ -134,7 +134,6 @@ void libfloat_reload_state(libfloat_ctx_t *ctx)
 
         iterator = kh_put(libfloat_entry_id_t, ctx->persistent.log, log->id, &absent);
         kh_value(ctx->persistent.log, iterator) = log;
-        ctx->last_log = log;
     }
 }
 
diff --git a/snapshot.c b/snapshot.c
index d9025d3..e602ed3 100644
--- a/snapshot.c
+++ b/snapshot.c
@@ -37,7 +37,6 @@ static void libfloat_internal_snapshot_apply_log(libfloat_ctx_t *ctx)
             libfloat_log_add_node_ack(ctx, entry, ctx->me->id);
 
         ctx->timeout_elapsed = 0;
-        ctx->last_log = entry;
         libfloat_set_current_commit_index(ctx, entry->id);
 
         if (entry->commit_type == LIBFLOAT_EVENTUALLY_CONSISTENT)
-- 
2.38.1