diff --git a/port/linux/api-make-linux.sh b/port/linux/api-make-linux.sh
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diff --git a/port/linux/api-make-win10.sh b/port/linux/api-make-win10.sh
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diff --git a/port/linux/api-make.sh b/port/linux/api-make.sh
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diff --git a/port/linux/gtest.sh b/port/linux/gtest.sh
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diff --git a/port/linux/init.sh b/port/linux/init.sh
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diff --git a/port/linux/make.sh b/port/linux/make.sh
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diff --git a/port/linux/package/pikascript/rust-msc-latest-linux b/port/linux/package/pikascript/rust-msc-latest-linux
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diff --git a/port/linux/pull-core.sh b/port/linux/pull-core.sh
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diff --git a/port/linux/push-core.sh b/port/linux/push-core.sh
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diff --git a/port/linux/test-banchmark.sh b/port/linux/test-banchmark.sh
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diff --git a/port/linux/test/mem_pool_config.c b/port/linux/test/mem_pool_config.c
index 7131c9fd1..5c5bf125b 100644
--- a/port/linux/test/mem_pool_config.c
+++ b/port/linux/test/mem_pool_config.c
@@ -1,5 +1,6 @@
 #include "dataMemory.h"
 
+#define use_mem_pool 1
 #define pika_aline 8
 #define pika_pool_size 8192
 uint8_t pika_bitmap[pika_pool_size / pika_aline / 8] = {0};
@@ -8,7 +9,6 @@ Pool pikaPool = {.aline = pika_aline,
                  .bitmap = pika_bitmap,
                  .mem = pika_pool_mem,
                  .size = pika_pool_size};
-#define use_mem_pool 1
 #if use_mem_pool
 void* __impl_pikaMalloc(size_t size) {
     void* mem = pool_malloc(&pikaPool, size);
diff --git a/port/linux/update-compiler.sh b/port/linux/update-compiler.sh
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diff --git a/src/dataMemory.c b/src/dataMemory.c
index c78847db5..691239e7e 100644
--- a/src/dataMemory.c
+++ b/src/dataMemory.c
@@ -205,7 +205,17 @@ void pool_free(Pool* pool, void* mem, uint32_t size) {
     /* save last free block index to add speed */
     uint32_t block_end = block_index + block_num - 1;
     if (block_end == pool->purl_free_block_start - 1) {
-        pool->purl_free_block_start = block_index;
+        uint32_t first_pure_free_block = block_index;
+        /* back to first used block */
+        if (0 != first_pure_free_block) {
+            while (0 == bitmap_get(pool->bitmap, first_pure_free_block - 1)) {
+                first_pure_free_block--;
+                if (0 == first_pure_free_block) {
+                    break;
+                }
+            }
+        }
+        pool->purl_free_block_start = first_pure_free_block;
     }
     return;
 }