perf: greatly increase the amount of tiles being read so nodejs start…

…up time affects the timing less

.hyperfine.json

@@ -1,6 +1,6 @@
 [
     {
-        "name": "Read 300 tiles from sparse.tiff",
+        "name": "Read 15,000 tiles from sparse.tiff",
         "command": "node packages/core/build/__benchmark__/cog.read.benchmark.js packages/core/data/sparse.tiff"
     }
 ]

packages/core/src/__benchmark__/cog.read.benchmark.ts

@@ -1,10 +1,13 @@
+import { SourceMemory } from '@chunkd/core';
+import { readFile } from 'fs/promises';
 import { CogTiff } from '../cog.tiff.js';
-import { SourceFile } from '@chunkd/source-file';
 
 /** Read a tile from every image inside of a tiff 300 tiles read */
 async function main(): Promise<void> {
-    for (let i = 0; i < 50; i++) {
-        const tiff = new CogTiff(new SourceFile(process.argv[process.argv.length - 1]));
+    const buf = await readFile(process.argv[process.argv.length - 1]);
+    const source = new SourceMemory('buf', buf);
+    for (let i = 0; i < 5_000; i++) {
+        const tiff = new CogTiff(source);
         await tiff.init();
 
         // 6 images

packages/core/src/cog.tiff.ts

@@ -78,13 +78,7 @@ export class CogTiff {
 
         const ghostSize = nextOffsetIfd - this.cursor.currentOffset;
         // GDAL now stores metadata between the IFD inside a ghost storage area
-        if (ghostSize > 0 && ghostSize < 16 * 1024) {
-            // logger?.debug(
-            //     { offset: toHexString(this.cursor.currentOffset), length: toHexString(ghostSize) },
-            //     'GhostOptions',
-            // );
-            this.options.process(view.bytes(ghostSize));
-        }
+        if (ghostSize > 0 && ghostSize < 16 * 1024) this.options.process(view.bytes(ghostSize));
 
         return this.processIfd(nextOffsetIfd);
     }
@@ -136,16 +130,15 @@ export class CogTiff {
     }
 
     private async processIfd(offset: number): Promise<void> {
-        if (!this.source.hasBytes(offset, 4096)) await this.source.loadBytes(offset, 4096);
-
         const { image, nextOffset } = await this.readIfd(offset);
         this.images.push(image);
 
         if (nextOffset) await this.processIfd(nextOffset);
     }
 
     private async readIfd(offset: number): Promise<{ nextOffset: number; image: CogTiffImage }> {
-        if (!this.source.hasBytes(offset, 1024)) await this.source.loadBytes(offset, this.source.chunkSize);
+        if (!this.source.hasBytes(offset, 4096)) await this.source.loadBytes(offset, 4096);
+
         const view = this.cursor.seekTo(offset);
         const tagCount = view.offset();
         const byteStart = offset + this.ifdConfig.offset;