diff --git a/src/fe_utils/astreamer_gzip.c b/src/fe_utils/astreamer_gzip.c
index df392f67cab..5b3c3a17550 100644
--- a/src/fe_utils/astreamer_gzip.c
+++ b/src/fe_utils/astreamer_gzip.c
@@ -247,6 +247,8 @@ astreamer_gzip_decompressor_new(astreamer *next)
 
 	streamer->base.bbs_next = next;
 	initStringInfo(&streamer->base.bbs_buffer);
+	/* Use a buffer size comparable to the other decompressors */
+	enlargeStringInfo(&streamer->base.bbs_buffer, 256 * 1024 - 1);
 
 	/* Initialize internal stream state for decompression */
 	zs = &streamer->zstream;
diff --git a/src/fe_utils/astreamer_lz4.c b/src/fe_utils/astreamer_lz4.c
index 605c188007b..12dfde2c837 100644
--- a/src/fe_utils/astreamer_lz4.c
+++ b/src/fe_utils/astreamer_lz4.c
@@ -288,6 +288,8 @@ astreamer_lz4_decompressor_new(astreamer *next)
 
 	streamer->base.bbs_next = next;
 	initStringInfo(&streamer->base.bbs_buffer);
+	/* Use a buffer size comparable to the compressor's */
+	enlargeStringInfo(&streamer->base.bbs_buffer, 256 * 1024 - 1);
 
 	/* Initialize internal stream state for decompression */
 	ctxError = LZ4F_createDecompressionContext(&streamer->dctx, LZ4F_VERSION);
diff --git a/src/fe_utils/astreamer_zstd.c b/src/fe_utils/astreamer_zstd.c
index 4b43ab795e3..98e8a700efe 100644
--- a/src/fe_utils/astreamer_zstd.c
+++ b/src/fe_utils/astreamer_zstd.c
@@ -82,7 +82,7 @@ astreamer_zstd_compressor_new(astreamer *next, pg_compress_specification *compre
 
 	streamer->base.bbs_next = next;
 	initStringInfo(&streamer->base.bbs_buffer);
-	enlargeStringInfo(&streamer->base.bbs_buffer, ZSTD_DStreamOutSize());
+	enlargeStringInfo(&streamer->base.bbs_buffer, ZSTD_CStreamOutSize());
 
 	streamer->cctx = ZSTD_createCCtx();
 	if (!streamer->cctx)